SMTP.com
Reliable SMTP relay and email delivery services. Powerful email delivery services that enable you to send and track high volume emails effortlessly. Integrate and start sending in minutes. All your transactional, email relay and email delivery needs under one roof. Whether you need a low-latency email delivery provider for your transactional emails, scalable infrastructure for high-volume sends or reliable backend solution for your marketing campaigns, SMTP is built to deliver. Reputation Defender is SMTP’s proprietary technology that uses big data to proactively monitor your email list health and safeguard your domain and IP reputation among ISPs by suppressing bad emails in your sends from hard and soft bounces. This ensures your delivery rates and inbox placement incrementally gets better over time.
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Volanea
Volanea is an email platform that combines transactional and marketing email in one product, so teams don't pay for two separate vendors. Built on Amazon SES, it provides a REST API and SMTP relay for transactional sends — password resets, receipts, OTPs, alerts — with delivery, bounce, complaint, open and click tracking on every message. For marketing, there's a drag-and-drop template builder, contact lists with segmentation, campaign scheduling, and event-triggered automated workflows. Deliverability is first-class: custom sending domains with your own DKIM keys (BYODKIM), SPF/DMARC setup guidance, shared or dedicated IPs with automated warmup, and reputation monitoring that throttles sending before bounce or complaint rates damage your domain. Templates, campaigns and workflows are separate reusable objects, so one template can serve both an API call and a broadcast. Pricing is credit-based — you pay for emails sent, not contacts stored.
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Cllavio
Cllavio is a high-deliverability email marketing and transactional email platform designed for startups and growing businesses. It includes a fast campaign builder, a powerful SMTP and REST API, clear analytics, AI-powered spam detection, and domain warming tools to help your messages reach inboxes.
With automated bounce monitoring, DKIM/SPF/DMARC validation, Shopify integrations, and predictable pricing, Cllavio makes it easy to send newsletters, cold emails, bulk campaigns, and transactional notifications from a single dashboard. It's designed for teams that want speed, reliability, and scalable email delivery without the enterprise complexity.
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Sidemail
Sidemail is a simple and reliable email platform that combines transactional emails, newsletters, marketing campaigns, and automations in one place. It offers a clean API for sending transactional emails, a no-code editor with automatic branding (logo + colors), email sequences, subscriber management, and solid deliverability — all at a fair price.
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