Alternatives to HELO
Compare HELO alternatives for your business or organization using the curated list below. SourceForge ranks the best alternatives to HELO in 2026. Compare features, ratings, user reviews, pricing, and more from HELO competitors and alternatives in order to make an informed decision for your business.
-
1
InboxAlly
InboxAlly
We engage with your emails to teach inbox providers not to send your emails to spam. Our clients have seen their open rates more than DOUBLE within 1-2 weeks! Highly engaged recipients not only open emails, but scroll down as they read. So long as the content is longer than the page, this should be done for nearly all opened emails. When a recipient goes out of their way to take an email out of spam, they are telling the inbox provider, hey, you made a mistake. Moving an email from the promotions folder to the primary inbox tells inbox providers that you disagree with their sorting criteria and it and similar emails should go to the primary inbox. Demonstrates that recipient is interested in the content of your email. We have a set of random generic replies we use for this. Marking an email as important can essentially be interpreted by the inbox provider as "This email is extremely valuable, never send it to spam." -
2
SendGrid
Twilio SendGrid
Email is the backbone of your customer engagement. The Twilio SendGrid Email API is the email service trusted by developers and marketers for time-savings, scalability, and delivery expertise. Our flexible Email API and proprietary Mail Transfer Agent (MTA), intuitive console, powerful features, and email experts make it easy to ensure all your email gets delivered in seconds and without interruption. Monitor engagement data and optimize deliverability with our Deliverability Insights dashboard. Whether you’re sending 100 emails or 100 billion, SendGrid is built to scale. Integrate with our RESTful APIs and SMTP in minutes, with sample code libraries available in 7 languages, interactive docs, templates, and more.Starting Price: $19.95 per month -
3
Stripo.email
Stripo
Stripo is an all-in-one email design platform with over 1 600 000 users worldwide. We enable our clients to build emails of any complexity really fast and push them to their marketing automation system with just 1 click. Integrated with 90 ESPs/CRMs, including Mailchimp, HubSpot, Salesforce, Campaign Monitor, Constant Contact, Braze, SendGrid, eSputnik, Outlook, Gmail, etc. +1600 ready-to-use templates, modular email design, Email Translate Service. A number of embedded micro-tools give everything you need for emails, from photo editors to banner generators, from timers to interactivity and real-time content. We are one of the first builders that implemented the AMP4Email technology. Multiple studies show that AMP increases conversion by 5 times. With Stripo, you can build real-time content for your emails with little to no coding skillStarting Price: $20/month -
4
GlockApps
GlockApps
Where are your emails delivered? Receive reports with an in-depth understanding of what your emails are doing and how to increase your reputation and deliverability before you hit Send! In your reports you can: ❖ Check to see if your sending IPs or Domains are listed within 50+ major email blacklists. ❖ Protect your identity by identifying, monitoring, and rejecting unauthenticated outgoing emails. ❖ Identify whether your email’s content or reputation is being flagged as Spam by all major B2B and B2C email marketing providers. ❖ Fix HTML errors and identify “risky” content before sending. ❖ Get instantly notified when issues occur by email, Slack, or Telegram. Want to speak with an expert? Book a 1-hour consulting call to get all your email marketing and deliverability questions answered. We also offer comprehensive Email Deliverability Audits with personalized recommendations for companies looking to maximize their revenue with email.Starting Price: $9 per month -
5
MailHog
MailHog
Inspired by MailCatcher, easier to install. MailHog is an email testing tool for developers: Configure your application to use MailHog for SMTP delivery. View messages in the web UI, or retrieve them with the JSON API. Optionally release messages to real SMTP servers for delivery. See MailHog libraries for a list of MailHog client libraries. ESMTP server implementing RFC5321. Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920). Web interface to view messages (plain text, HTML or source). Supports RFC2047 encoded headers. Real-time updates using EventSource. Release messages to real SMTP servers. Chaos Monkey for failure testing. See Introduction to Jim for more information. HTTP API to list, retrieve and delete messages. See APIv1 and APIv2 documentation for more information. HTTP basic authentication for MailHog UI and API. Multipart MIME support. Download individual MIME parts. In-memory message storage. MongoDB and file-based storage for message persistence. -
6
HTML Email Check
HTML Email Check
HTML Email Check includes all the tools developers need to create, check and validate their HTML emails with, including instant validation results, an integrated HTML editor, layout viewer, and email sending. Validation of the HTML markup, structure, and client-specific tags. Validation of CSS formatting, inline CSS, and client-specific styling. Validation of font types, web fonts, and client-specific styling. Checking of image sources, dimensions, and attributes. Checking for working URL's, special links, and attributes. Layout and HTML structure testing on non client-specific devices. Send up to 10 test emails at a time directly to your inbox. Covering important aspects your email should include before sending. Every day is different and sometimes you need to react quickly to a certain situation or last-minute changes.Starting Price: $14.95 per month -
7
Debug Mail
DebugMail.io
How Debug Mail work The service provides command-line access to the virtual SMTP-server. The sender and receiver addresses can be anything, since no real mailings are sent. The technology used by application developers does not matter, the service will work with PHP, Python, Ruby, Node.js, .NET and many other programming languages and frameworks. Sharing options Sharing is the main feature of Debug Mail. To see what the service and other mailings will look like, just connect the right users to the project in the service, and they will see the same thing as the developer who is testing the mailing. What you can do in Debug Mail - Send emails to non-existent test addresses instead of real ones. - Set up email distribution lists with colleagues using team access. - Work together with other developers on the service.Starting Price: $2 per user per month -
8
Minty Email Tester
MintyEmailTester.com
Minty Email Tester sends HTML email code to users' inboxes to check for rendering issues across different email providers like Gmail, Outlook, and Yahoo. Key Features: • Send test emails to multiple providers simultaneously • Save up to 10 email addresses to avoid retyping recipient lists • HTML validation checks for missing or malformed alt attributes on images • Table role validation and malformed HTML detection • Automatic CSS inlining for better email client compatibility Pricing: Free tier (5 emails/month) and Pro subscription ($9/month) for unlimited testing and advanced features.Starting Price: $9/month -
9
SMTP Debug Tool
SMTP Debug Tool
Ensure flawless email communication with the SMTP Debug Tool, a completely free and secure way to diagnose SMTP connection issues. This tool connects to your SMTP server, initiates a test session, and provides a detailed log of the interaction between servers. Whether you're using popular email services like SendGrid, Google SMTP, Elastic Email, UniOne or Mailgun, this tool simplifies troubleshooting and helps resolve sending errors. With end-to-end encryption, your information remains private and secure. The tool doesn’t store any session logs or credentials, and you can further enhance security by changing your password after testing or using the optional “SMTP Blackhole” feature.Starting Price: $0 -
10
SendHealth
SendHealth
We generate an extensive report on sending IP, domain, their blacklist data, Content spam score, DNS records alignment for inboxing your emails. Once you have sent the email, start the diagnosis and we generate the report for you to understand and debug your email lords. Use your email marketing tool, ESP, API, or your GSuite/Zoho workspace to send an email to the recipient provided by us. The blacklist looks for domains in the email body that have been a known source for spammers. These domains will not be just in an initial link but in the final redirected link too. RBL and DNSBL are used to identify whether the IP of the sending server is an open relay that has been used by spammers or is by an ESP that allows spammers to use their infrastructure. -
11
Mailtrap
Railsware
Mailtrap is an email delivery platform for developers and product teams, providing a flexible RESTful API and SMTP service to send emails at scale. The platform is built with a focus on high inboxing rates, fast delivery, and 24/7 technical support from deliverability experts. Mailtrap ensures 99.99% uptime with dedicated IPs, auto warm-up, and sender reputation protection. Developers can integrate quickly using SDKs for major languages (Python, Ruby, PHP, etc.) and manage high-volume sending with a customizable API. The platform provides industry-best analytics with helicopter-view dashboards to monitor key metrics and 30-day logs for easy debugging. Trusted by over 150,000 monthly active users including Yelp, PayPal, Atlassian, and Adobe.Starting Price: $15/month -
12
Mailcatch
Felis Studio
Mailcatch.app offers a streamlined solution for testing emails. Whether you're a developer keen on refining your email sending features or a marketer looking to perfect your campaigns, this tool is designed with you in mind. **Quick Start**: 1. Choose from over 20 code samples or just copy the SMTP details. 2. Integrate the configuration into your project. 3. Trigger your email sending function. 4. Instantly see your message in the inbox. With Mailcatch, email testing has never been more straightforward or efficient. Experience a hassle-free email testing journey today. Supercharge your marketing ✨Starting Price: $14.99 per month -
13
MailSlurp
MailSlurp
Create unlimited private email addresses on demand in code, tests, or online. Send and receive emails and attachments and process emails with HTTP Webhooks, Zapier integrations, and team dashboards. Test user authentication, forgotten password, email verification and more for your application using real email addresses. Use REST API, developer SDKs, and Zapier integrations to receive emails in code, test user sign up flows, and save new contacts and attachments to Google Drive and more. Generate inboxes with custom domains or randomly assigned email addresses. View emails and attachments in code, tests, or using team web apps. Process text messages for real phone numbers using webhooks and REST APIs. Send and receive emails in code or tests using webhooks or waitFor function. Search and match emails. End-to-end test applications using real email addresses.Starting Price: $22.80 per month -
14
Litmus
Litmus Software
Build, edit, and instantly preview your emails across 90+ clients. Plus, utilize integrations with popular email platforms to speed production and reduce errors. Catch broken links, images, and tracking, as well as test campaign load time, scan your subject line for improvements, and more with a simple, automated check. Quickly identify potential issues preventing your email from being delivered, and use actionable in-product advice to fix them.Starting Price: $99 per month -
15
MailMonitor
MailMonitor
Knowing exactly where your campaigns are going to land is important, but ensuring they reach your subscribers’ Inbox is a game-changer. Email Marketing is about building trust with internet server providers. Tracking your reputation and keeping it strong helps improve your email deliverability. Solving your email deliverability issues starts with tracking your reputation. Find out how the largest spam filter companies rate your campaign. Blocklists can significantly hurt your reputation. Monitoring your IP addresses and domains help you take immediate action and delist if you get blocklisted. Reinforcing email authentication provides the strongest email domain protection, ensuring proper deliverability to all your email campaigns. Customer experience is key to all first-class brands. Email previews help you detect bad formatting, broken links and code issues, before they reach the Inbox.Starting Price: $299 per month -
16
Folderly
Folderly
AI-based email deliverability platform for monitoring, spam testing, and maintaining your email deliverability by solving any spam issues. Our goal is to help marketers accelerate their sales by assisting them in sending emails that drive revenue. Over 51% of all business emails worldwide never reach the inbox. Losing your emails to spam folders ultimately leads to budgeting issues and missed sales opportunities. Folderly makes sure that you're never in that 51%. Avoid blacklists, bypass spam filters, and see your messages delivered to your email recipients’ inboxes. We designed Foldely from the ground up to help companies receive returns on their marketing dollars. Whether you're looking to increase the email deliverability of your emails across multiple email addresses, or want to prevent any spam-related problems before they occur - Folderly is a great starting point to make sure your messages are reaching your recipients' inboxes.Starting Price: $160 per month -
17
Imitate Email
Imitate Email
Imitate Email is an end-to-end email testing platform for developers and QA teams to ensure their email flows happen at the right time and look great. Where we differ is with our embeddable web widget and SSO feature. A single line of JavaScript adds the Imitate Email widget to your application so that: - developers can test email flows inside the software they're building - testers, or clients, can see emails inside the software they're testing without needing an Imitate Email account On top of this, we provide all the features you would expect: - a web app for viewing emails - tools for checking responsiveness, link checking, spam scoring and deliverability - a fake SMTP server alongside dedicated test email address - IMAP/POP3 access for use with your favorite email client or programmatically - integration testing support with IMAP/POP3 and WebSockets - and more! Free forever for solo developers with 15 emails a day and access to all featuresStarting Price: $7/month -
18
Email on Acid
Sinch
Our three-step workflow fits into your existing production process, making it easy to save time, drive value, and connect with more subscribers. Deliver error-free emails with the push of a button—no HTML experience required! From UTM validation, and accessibility checks that ensure ADA compliance, to validating and replacing the first frame of animated GIF’s for Outlook, we offer customizable click-to-fix tools that fit your team’s specific requirements. Subscribers can’t engage with your campaigns if they don’t receive them. Improve your email deliverability—and land in more inboxes—with blocklist domain and spam tests. Check your email against 23 of the most popular spam filters and test your IP address against the most popular blocklist services. Resolve any deliverability issues before you click “send.” Every inbox displays emails differently. With previews on over 90+ clients and devices, we help you make certain your message displays as intended—in every inbox.Starting Price: $86 per month -
19
Mailosaur
Mailosaur
Mailosaur lets QA and Development teams capture, test and analyze email and SMS messages using their existing test framework or language. Catch bugs before your customers do! Pinpoint defects in critical workflows, such as account activation and password resets before they get released. Mailosaur is a key addition to any reliable suite of test tools or frameworks, giving you full confidence in the most critical workflows of your application. Use a new email address for every test run, project, team member, or idea you have! Integrate the results into your existing test framework. Create phone numbers that let you perform end-to-end tests of critical workflows, such as security verification checks. Build out real-world test scenarios that perform common user actions such as following links in emails, replying to messages and triggering web beacons. Prevent internal environments from sending externally, and never email a real customer by mistake!Starting Price: $9 per month -
20
ISnotSPAM
ISnotSPAM
Sending newsletters and email marketing is not easy. You need to work on the design, the graphics and the content. Being busy with all that work, you might forget to check if your content is set to trigger some spam filter which will send your hard work straight to the subscribers' spam folder. IsNotSpam online spam checker was created to help you test email and newsletter content, and alert if it is likely to trigger spam filters. 99.99% of email accounts use spam filters these days. Spam filters recognize spam messages by analyzing message content for spam characteristics. Sometimes these filters fail and mark legitimate emails as spam. Such emails are sent to the Spam folders and are not seen by the recipient. This filter failure is called a "false positive" as it marked a legitimate non-spam message as spam. Newsletter senders and email marketers need to check that their emails do not have spam characteristics in order to lower the risk of their newsletters being marked as spam. -
21
Inbox Pirates
Crewcharge Technologies
Inbox Pirates is an email preview, email testing & subject line testing software tool that powers email marketing and sales outreach teams to get a great boost in email opens. It previews your email on popular email clients like Gmail, Yahoo, and Outlook, and on several devices and screen sizes. Inbox Pirates allows you to preview, test, and analyze emails using the chrome extension and integrates with popular mailing tools like Hubspot, Apollo.io, Brevo, Mailchimp, and Gmail. It allows you to fix broken HTML emails. With NLP and AI - Inbox Pirates creates an email checklist with your email's reading time, character count, word count, spelling mistakes, and checks for accessibility issues to grade your emails and generate an email score. You can also preview your emails on notification bars, inbox views (when stacked up with other emails), and when it's open on various smartphone devices like iPhones and Google Pixels.Starting Price: $0 -
22
Pacomail
Leikir Web
Pacomail is a test mail server solution that allows testing email without sending them to the real users of your application. Code, preview, test, and collaborate using a development tool designed for email.Starting Price: €15/month -
23
Mailsac
Forking Software
Make up any email address @mailsac.com and you can instantly receive mail. No need to create the email first! Everything is public, unless you create an account. It's cheap and easy to setup a unique email address per online service. Route all your Mailsac addresses to a single one that you check. Email validation checks the formatting of an email address and if the email address is associated with a known disposable email address provider. With Mailsac, it is easy to interact with email via REST API, Webhooks and WebSockets. You can reserve and release email addresses, check messages, download attachments, and route mail. Email attachments are not viewable for public addresses from the Website. Attachments must be downloaded using REST API. Attachments on emails sent to Private Addresses can be viewed in the Unified Inbox or in an email client using POP3. -
24
PutsMail
Litmus
Test your HTML emails before sending them! Once you’ve run a few tests with Litmus PutsMail, check out Litmus' full email testing suite to ensure an on-brand, error-free subscriber experience. Litmus helps you get more out of your emails with the power to test and preview in 90+ email clients—including Dark Mode—in one spot. In seconds. Litmus provides the leading email optimization and collaboration solution for marketers. From Pre-send campaign development and testing to Post-send insights for future content optimization, Litmus improves marketing performance and strategy, delivering increased subscriber engagement. -
25
Mailinator
Manybrain
Test your trial sign ups, account creation, marketing Emails, and SMS for interactions and receipts at production scale - instantly! Upgraded plans get private inboxes at private domains unique to your account, Web and API access, message routing rules, permanent storage, and high daily limits. Mailinator is really, really good at Email. But it handles any kind of Message. You can add an SMS to your Private Domain(s) for SMS Workflow Testing. Or have a third-party send their JSON Payloads right to your inboxes! Save your teams time by never having to create an email address. With Mailinator, every possible email address (at your Private Domain) is available to use right away Access all your messages via our Web Interface, our API, or have Mailinator automatically Webhook them back to you. Our Rule system can also Click-Links, Forward, and more!Starting Price: $99 per month -
26
Zyntra
Zyntra
Zyntra is a disposable email platform for QA teams and test automation workflows. It helps you capture, assert, and validate email content as part of your end-to-end tests — without manual setup or flaky workarounds. Use it to: • Generate unlimited private inboxes automatically, with one line of code • Trigger real emails (OTP, password resets, invites) and read them via API or Web viewer • Prevent test emails from leaking to real users — all inboxes are private by default • Run isolated tests in CI/CD with no collisions or cleanup • Validate your entire email-based flow, just like in production (real SMTP) Zyntra works with any testing framework or language and includes an official Node.js SDK for fast integration. Ephemeral inboxes are retained for 24 hours; persistent ones for at least 7 days. Built by QA, for QA — Zyntra helps you stop babysitting test environments and focus on verifying what matters.Starting Price: $9/10000 emails/month -
27
PilotMail
Netling Digital
Code awesome HTML emails and test them easily on real email clients before sending with PilotMail. PilotMail comes with a split-screen layout viewer and code editor that's designed specifically for building HTML email. Code Editor lets you code email template's HTML-Part, Text-Part and even CSS all at one place. Layout Viewer helps you in live email visualization for desktop, tablet, and mobile devices. For the best HTML e-mail delivery results, CSS should be inline. PilotMail can do it automatically every time you send a test email. That's not all. PilotMail has many other handy settings to pre-process your code and make it ready for use in production. Setup up to 10 email addresses for a test, where, each email address can represent an email client. PilotMail will send HTML email to all email addresses at once for you to find issues on live email clients.Starting Price: $3 per month -
28
mailnest
MailNest
The world's easiest email testing tool. Save time, effort and money while concentrating on your application's core features. Capture all your test emails in one place. No more accidental sending of test emails to real customers. Add all your team members to collaborate easily. Check the spam score to ensure mails reach customer inbox for sure. Setup a virtual smtp server in 2 minutes. Test multiple scenarios without creating multiple email ids or clearing database. View source code of emails to check everything is perfect. Switch on error mode to emulate error scenarios. Preview all emails in a single place. Check for multiple device compatibility with a single click. Include email testing in your automation. No need for creating multiple email ids for various scenarios.Starting Price: $35 per month -
29
Inbox Monster
Inbox Monster
Inbox Monster helps email teams send epic messages to every inbox. With creative rendering and deliverability tools, you can find your email rawwwr. Expert Services: Truth: You need an expert by your side. Sending email is a lot. And the rules are constantly changing. That’s why having proactive support to help you make it to the inbox is just worth it. For your sanity and bottom line. Creative Suite: Creative testing, with a glow up. We’re doing email testing a little different. There’s a new way to test out your email creative. Get previews of your emails, plus killer diagnostics to help you get closer to perfect. So you can send with confidence. Not sweaty palms. Deliverability Suite: Don’t be a spammer. Like ever. Deliver more from your email program. More emails in the inbox. More revenue from your program. More kudos from your boss. Get the new way to dig into all aspects of your email deliverability. SMS Suite: Reach the phone obsessed. (So, everyone.) Flawless -
30
MailTester
MailTester.com
In just one year, 20%-30% of email addresses bounce. With MailTester.com email verifier, verify email and get rid of those invalid emails from your database with 99% accuracy. You want better ROI from your email campaigns and refuse to spend any money on invalid or discarded emails. You want excellent email deliverability. You expect your emails would reach right inboxes every time. You want an accurate, efficient and secured email list cleaning service. Your email campaigns couldn’t drive results if your list is full of invalid email addresses. You would have to pay for emails that won’t get delivered ever. Scrub your list with MailTester.com email verifier, remove those unwanted emails and watch your ROI increase. Toxic emails can creep into your email lists in many ways may be a visitor mistyped his email or someone used a non-corporate email to get that super useful lead magnet you offer. Catch those irrelevant and invalid emails with MailTester.com API.Starting Price: $19 per 5,000 emails -
31
Accessible-mail.org
Accessible-mail.org
It is the mission of Accessible-email.org to promote email marketing accessibility and usability. In that be the voice of users and the email marketing community. For years the email marketing industry has never really made a point of accessibility. But a large section of email recipients does care and need accessible email. With the current maturity of the channel, it should be totally possible and new devices, email clients and coding techniques demand better accessibility. We believe it is the right time to get more serious about the topic to keep the channel open for the future. The accessibility evaluation tool is the first of our projects. It is aimed at email marketing professionals and industry developers to give them an overview of their current level and possible improvements. -
32
Mailgun
Sinch
Mailgun is an email automation solution that is suitable for developers. With Mailgun, users are able to access a complete cloud-based email service for tracking, sending, and receiving emails sent via their applications and websites. Mailgun supports several programming languages including Python, Ruby, PHP, Java, and C#. With Mailgun's tracking feature, users are able to track all emails and reduce the chances of getting spam.Starting Price: $0.01/month/user -
33
SendForensics
SendForensics
On average, 30% of emails fail to reach their target by dropping straight into customers' spam folders. Reclaim this lost revenue with the most advanced email deliverability system available. The SendForensics Deliverability Score is a unique, predictive modeling of an email's ability to reach any given inbox. To put it simply, it is a measure of an email's 'quality' in terms of how it will be perceived by global filtering-systems/ISPs and even human recipients themselves. Truly the Missing Metric. From email content, to the sending infrastructure, reputation, engagement-history, external feeds (such as Microsoft SNDS*) and more, SendForensics EDS automatically sifts through the datasets to present the biggest cause(s) for concern at every analysis.Starting Price: $49 per user per month -
34
mail-tester
mail-tester
We needed a cheap, simple and efficient way to quickly test the quality of our own newsletters. We simply built on our own tool. Now we're sharing it for free via our web-interface and enable you to include our tests in your own app and whitelist our service by creating an account. We're geeky email software engineers. We generate a random email address each time you access our port. You should send a message from your favorite Newsletter/email software to this email address. Once done, click on the check your score button and as soon as we receive your message, our snail will stop to give you your spam score. Mail-tester will analyze your message, your mail server, your sending IP and show you a detailed report of what's configured properly and what's not. All spam filters work differently. What may pass in mail-tester, might not in your own office inbox. It also depends on user preferences.Starting Price: €50 per 500 test -
35
Maileroo
Maileroo
At Maileroo, we provide a powerful platform for both SMTP relay and email marketing. We ensure fast, reliable email sending with real-time tracking of deliveries, clicks, opens, and bounce rates. With our free Email Verification API, dedicated IPs, and DNS Records for sender authentication, we help reduce bounced emails and improve deliverability. Our email marketing platform makes it easy to create and manage campaigns. You can personalize emails, use our drag-and-drop email templates, form builders, and flexible Contacts API. We provide real-time statistics and in-depth analytics to help you optimize your campaigns and boost engagement. We also offer seamless DNS setup, automation tools, multi-sender identities, and efficient contact management. Whether you're a small business or growing enterprise, Maileroo offers budget-friendly pricing and everything you need to scale your email marketing, making it a smart choice for businesses of all sizes.Starting Price: $10 per month (25,000 emails) -
36
Warmup Inbox
Warmup Inbox
Warmup Inbox automatically raises your email sending reputation through our network of inboxes that talk to each other. The process of preparing an email address for general use or email outreach is commonly referred to as “Warming Up” an inbox, where you take a number of steps to ensure that an email address does not become deactivated, blacklisted, or automatically marked as spam when it begins to send outgoing messages to other recipients. This process is typically done with newly created email addresses but also benefits older email addresses who have been having issues with email deliverability, in that a noticeable portion of their outgoing mail is either landing in a spam folder or blocked entirely by an email server due to either being blacklisted or associated with a domain that has a poor reputation. Warming Up an email inbox essentially is recreating the way a typical person will use an email address.Starting Price: $19 per inbox per month -
37
Arnica EmailServer
Arnica Software
Arnica EmailServer is an enterprise-strength tool for automating both mass-emailing and single email processing tasks. Arnica EmailServer also provides functionality for performing either scheduled or on-demand download of incoming emails for multiple accounts and storing them in easy-to-access database tables through specially created database APIs. All email queue, mass-mail and incoming email management is done through a web browser interface. Arnica EmailServer allows you to avoid direct interfacing with low-level SMTP subsystems by providing a high-level easy-to-use application programming interface. You may publish emails into an outgoing queue (or mark them to be sent immediately) using web requests with posted XML provided by Arnica EmailServer, which includes email content together with sender/recipient information as well as other data required for sending an email. -
38
VIPRE SafeSend
VIPRE Security Group
Protect your organization from accidental data breaches with VIPRE SafeSend, the ultimate safeguard for Microsoft Outlook. SafeSend prompts users to confirm external recipients and attachments before sending emails, reducing the risk of misaddressed messages. Unlike traditional Data Loss Prevention (DLP) solutions that simply block emails after they’re sent—adding strain to already overstretched security teams—SafeSend proactively empowers employees to recognize and prevent mistakes in real time. It also scans outgoing emails and attachments to ensure sensitive data stays within your network. Over time, users develop better email habits, enhancing your organization’s security posture. Choose from two tailored packages: one focused on preventing misaddressed emails and another designed to meet comprehensive DLP requirements. With VIPRE SafeSend, you’re not just protecting data—you’re building a smarter, more security-conscious workforce.Starting Price: $30/user/year -
39
AuthSMTP
AuthSMTP
AuthSMTP is the outgoing SMTP email service for your e-commerce website, mailing list or email application on most current computers and mobile devices. With instant setup, a money back guarantee and very low cost starter accounts you can test and start sending email in minutes with no risk. Our systems are custom designed / built for reliability and performance when processing and delivering very high volumes of email. We use high performance and redundant systems to help ensure we can provide the highest levels of availability. We provide an online Control Panel plus email and web based support backed by knowledgable support staff on hand to provide help if required. We have over 15 years experience providing email services and getting emails delivered quickly and accurately to your recipients.Accounts are created instantly when you sign up so with our setup guides you can start sending email within minutes.Starting Price: $36 per year -
40
SMTP2GO
SMTP2GO
Send and track all emails easily and securely with SMTP2GO, a reliable outgoing email service solution. SMTP2GO features a redundant, multi data center infrastructure that allows users to send emails even if there is a major internet outage. SMTP2GO has features like real-time analytics, bounce/spam tracking, weekly summaries, spamtrap detection, blacklist monitoring, DKIM/SPF, and more.Starting Price: $10 per month -
41
testmail.app
testmail.app
Get unlimited email addresses and mailboxes for automating end-to-end tests with our simple APIs. Email verifications, passwordless signins, etc. Are they triggering when expected? Are emails reaching the inbox? Never spam real customers by mistake - send your test emails to {namespace}.{tag}@inbox.testmail.app. Signup to get your {namespace}. The {tag} can be anything: each tag makes a separate email, so you can create unlimited real email addresses and mailboxes on the fly by simply changing the tag! Use any HTTP or GraphQL client of your choice in any language or environment including CI/CD pipelines. Take it further with awesome features like advanced search with wildcard match, "live" queries (waiting for new emails), sorting, pagination, attachments, SpamAssassin reports, and more. Together you can create separate namespaces (and mailboxes) for each project, securely provision and retrieve API keys, share test emails, monitor usage, and manage team membership.Starting Price: $9 per month -
42
Password.link
Password.link
The link can only be opened once. This ensures nobody has opened it before the recipient and nobody can open it again afterward. The encrypted secret is deleted from our database when it has been viewed. There's no way to view it again. Sending secrets in plain text exposes them to threats even after the message has been long forgotten. Using a one-time link ensures that there are no valid credentials lying around in email inboxes or archived instant messages. Half of the encryption key is stored in the link itself and never seen by us or anyone else. Viewing the secret is not possible without the original link. Using our service you can create a one-time link to the credentials and be sure nobody sees them before the recipient. You can also configure notifications to be sent via different channels so you know when the credentials have been viewed, and by who.Starting Price: €8.99 per month -
43
Bit SMTP
Bit Apps
Many site owners face the spam mail problem for using the WordPress default PHP mail function. There may be some restrictions when it comes to mail service: sometimes emails are not delivered, sites cross the limit of outgoing mail. Bit SMTP plugin allows you to authenticate the mail service of your site by configuring the SMTP server of your desired mail service. SMTP is a protocol that helps your WordPress site make its email deliverability more easygoing & reliable. By enabling this feature, you can send mail from your site to your recipients via your preferred mail server. -
44
Mocke
Mocke
Mocke (Mock Email Campaign) is an AI-powered tool for testing cold email strategies without sending real campaigns. Users upload a CSV file to launch a mock campaign in just one click and receive simulated outcomes, including reply rate, unsubscribe actions, report-spam flags, internal forwards, reminders, and ignores, in as little as one minute. This allows rapid AB testing of copy, subject lines, CTAs, and messaging, and uncovers hidden lead behaviors without launching real campaigns, saving over 99% of the time traditionally needed for testing while offering deep analytics and insights.Starting Price: $79 per month -
45
EmailPreviewServices
EmailPreviewServices
We are EmailPreviewServices company owned by Easy Tech Solution LLC. We offer a service with quality tools that allow us to preview email designs before they land in the recipient's inbox. Our tools also test emails for Spam and monitor Inbox status. Please note: we ONLY provide testing for real devices and email preview software. We do not use any simulators or emulators. Our all-around service offers something for everybody, so whether you are an entrepreneur, small business owner or a multi-national company - we have all the necessary tools and features for building a strong email campaign, ensuring that your emails work and convert traffic for you. Our main goal is to provide our customers with an actionable platform, by which they could quickly fix general content-viewing and email deliverability issues.Starting Price: $25 per month -
46
EmailGuard
EmailGuard
EmailGuard is an all-in-one email deliverability platform designed to help you never land in the spam folder again. It offers a suite of tools to increase your email deliverability while ensuring compliance. With EmailGuard, you can instantly connect and monitor your domain's SPF, DKIM, and DMARC records, and if any records are missing, you can look up, generate, and verify them in one place. It provides features like blacklist monitoring to keep an eye on your domain, IP addresses, and sending servers, notifying you instantly if you're listed and providing details to get delisted. The features allow you to mask your primary domain with multiple secondary domains, using a pool of shared IPs or your own dedicated IP. EmailGuard also includes an email tester that analyzes 162 different potential data points, passing your email through a series of deliverability tests and spam filters.Starting Price: $49 per month -
47
Testi@
Testi@
Looking for an alternative to preview your emails? Then check our great affordable tools. You can compare features, prices, email clients on: Comparison of Email testing tools page. T@ has no API for users so infrastructure is not so much overloaded. Prices on T@ are fantastic if you can pay 20$ for "browser Testing" then why for email previews you can't pay the same prices?. Our servers has almost 1,5TB of RAM that use enterprise SSD, connected by 10G network. Mobile devices are working in "spare" models when few crash another is replacing them. Using Testi@ is like renting an expensive supercar for a few dollars, it takes almost 3 years to develop and invest a lot of money to give you affordable email screenshot tools.Starting Price: £16 per month -
48
SubjectLine
SubjectLine
SubjectLine.com is a division of Worldata. Contact us today to receive more information about how we can help you and your company with your marketing strategies! SubjectLine.com has become the industry’s leading email marketing resource. The site includes major marketing related news items, best practices and a free subject line rating tool that allows marketers to test any subject line for possible deliverability and marketability issues. The tool scans for over 800 unique rules that could impact a marketer’s email open rates and deliverability. Results provide marketing-related suggestions that are based on 6 billion+ email messages checked, improving marketers overall campaigns. These results enable marketers to acquire new customers utilizing the best permission email data available, improve email customer data hygiene and depth and provide strategic consulting services for both retention and acquisition email efforts. -
49
Sweego
Mindbaz
Sweego is a multichannel (email & sms) notifications platform for developers. Sweego allows users to send transactional, engagement, and CRM messages through channels like email and SMS. The platform provides APIs and webhook system to integrate notifications and messaging capabilities into applications. (SAAS, Mobile, Desktop, whatever...) We offer SMTP Service or API to send emails or sms. We offer Inbound Email routing feature, we got email, parse it and deliver in JSON by webhook. With our email builder, you can create your template easily with drag and drop fonctionnality, HTML import, good email client compatibility, brand management, etc... Key features include message templates, email authentication, webhooks, sandbox testing for emails, statistics, logs and scalability.Starting Price: €10/month -
50
Instant Bulk SMTP
Instant Bulk SMTP
We understand how important role marketing plays in business and by looking that we have designed our Instant Bulk SMTP service which help to start sending your campaign in less than 30 minutes. Manage multiple contact lists, add, remove, delete, and import-export. Not only can you check bounces, opens, and click-throughs using our email analytics. You can set up or integrate with your applications. Easy to upgrade to a higher plan without any hassle. Instant Bulk SMTP is an outgoing email service that will allow you to send emails from your email address whether you have your own software or you don’t have your own software. We understand how important the role marketing plays in business and by looking at that we have designed our Instant Bulk SMTP service which helps to start sending your campaign instantly. Unlike typical email marketing services, our high-volume SMTP hosting service lets you send from your own application server, email client or a combination of different sources.Starting Price: $50 per month