Postmark
Email for web applications
Seamailer
Send emails that land in the inbox and bring results
Updated February 2026
| Postmark | Seamailer | |
|---|---|---|
| Rating | 5.0★ | 5.0★ |
| Reviews | 17 | 2 |
| Pros | 9 | 11 |
| FactScore™ | 62.8 | 23.9 |
FactScore™ Comparison
FactScore™ weighs both quality (rating) and popularity (reviews) for a fairer ranking than stars alone.
Pros & Cons
Only in Postmark — Pros
Reliable email delivery Fast performance Human support Transactional email Affordable pricing Email templates Excellent documentation Simple API Spam filterBoth tools — Pros
—Only in Seamailer — Pros
AI integration Automation High deliverability Newsletter creation Unlimited contacts Unlimited emails Conversion funnel Detailed reports Prompt customer support Robust features Small business inclusionOnly in Postmark — Cons
—Both tools — Cons
—Only in Seamailer — Cons
—Details
| Postmark | Seamailer | |
|---|---|---|
| Categories | Email clients, Email marketing | Email marketing, Marketing automation platforms |
| Platforms | Web · iOS | Web |
| Became Popular | July 23, 2014 | October 1, 2024 |
| Website | postmarkapp.com | www.seamailer.app |
Who Should Pick Which?
Choose Postmark if...
- Reliable email delivery
- Fast performance
- Human support
Choose Seamailer if...
- AI integration
- Automation
- High deliverability
With a FactScore™ of 62.8 vs 23.9, Postmark leads in community reception. Postmark uniquely offers Reliable email delivery and Fast performance, while Seamailer stands out for AI integration and Automation.
What Users Say
Postmark
We use Postmark to send emails and manage newsletters directly from BlogBowl. Big thanks to Postmark for their reliable API and top-notch deliverability, which makes sure your newsletters actually ...
We use Postmark not only for our emails, but also to power Ply's built-in dynamic email capabilities. It's reliable, well documented and most of all - comes with awesome human support.
Once you get familiar with Postmark's layouts and templates, the service is great for quickly creating email templates and sending them out using their simple API. The UI is simple and intuitive.
Seamailer
Seamailer solves the email marketing challenges I faced. Previously limited by sending capacity and budget, now with unlimited contacts and high deliverability, marketing is much more efficient.
Is very hard to find products including startups and small-scale businesses in their plan. Seamailer didn't just include us, they gave us premium access to grow our business. I love their robust fe...
Related Comparisons
Frequently Asked Questions
Which is better, Postmark or Seamailer?
Based on FactScore™, Postmark leads with a score of 62.8 vs 23.9. Postmark has a higher rating of 5.0★ compared to 5.0★.
What are the pros of Postmark compared to Seamailer?
Postmark uniquely offers: Reliable email delivery, Fast performance, Human support, Transactional email, Affordable pricing.
What are the pros of Seamailer compared to Postmark?
Seamailer uniquely offers: AI integration, Automation, High deliverability, Newsletter creation, Unlimited contacts.
Is Postmark better rated than Seamailer?
Postmark is rated 5.0★ from 17 reviews. Seamailer is rated 5.0★ from 2 reviews.
What is the FactScore™ of Postmark and Seamailer?
FactScore™ weighs rating and review volume together. Postmark scores 62.8 and Seamailer scores 23.9.
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