Audience

Web developers building applications that send transactional or automated emails and need a local tool to test, debug, and validate those emails before deployment

About HELO

HELO is a desktop application designed to simplify email testing and debugging for web developers by capturing and analyzing outgoing emails generated by applications during development. Instead of sending emails to real recipients, HELO exposes a local SMTP server that intercepts outgoing messages and displays them inside the application, allowing developers to inspect and verify them before deployment. This approach helps prevent common problems such as broken links, missing images, formatting errors, and other issues that often appear in production emails. It provides detailed debug views that show the email in multiple formats, including HTML rendering, plain text, raw source code, and full message headers, giving developers a complete understanding of how the message is structured. Automated validation tools check links within the email to confirm they return valid HTTP responses, reducing the risk of sending emails with invalid or broken URLs.

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Pricing

Starting Price:
$49 per month
Free Version:
Free Version available.

Integrations

See Integrations

Ratings/Reviews

Overall 0.0 / 5
ease 0.0 / 5
features 0.0 / 5
design 0.0 / 5
support 0.0 / 5

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Company Information

Beyond Code
Founded: 2017
Germany
usehelo.com

Videos and Screen Captures

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Product Details

Platforms Supported
Mac
Training
Documentation
Live Online
Videos
Support
Online

HELO Frequently Asked Questions

Q: What kinds of users and organization types does HELO work with?
Q: What languages does HELO support in their product?
Q: What kind of support options does HELO offer?
Q: What other applications or services does HELO integrate with?
Q: What type of training does HELO provide?
Q: How much does HELO cost?

HELO Product Features

Email Testing

Pre-Send Email Testing
Preview Across Browsers & Devices
HTML Validation
Spam Testing
Deliverability Rates
Accessibility Testing
Sender Reputation Scoring
Reporting / Analytics
A/B Testing
Improvement Recommendations
DMARC Analytics
IP Blacklist Checking