Spamcheck by Postmark
Automated spam score testing API and email header verification tool
pricingfree tierapichecked 23 Aug 2026
What Spamcheck by Postmark is
Spamcheck is an automated API and web tool powered by Postmark that evaluates email HTML and raw MIME payloads against Apache SpamAssassin rules. It returns an instant spam score with a detailed line-by-line rule breakdown, allowing email software developers to integrate automated pre-flight spam checks directly into their customer publishing applications.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Free API | Free | Unlimited web scans and open REST API calls, instant SpamAssassin score breakdown |
Free public developer tool and REST API provided by ActiveCampaign Postmark.
Free access: 100% free and open public REST API for developers
read from the vendor pricing page · 23 Aug 2026 · how we verify
Best for
- Developers integrating automated pre-send spam scoring into custom email software
- Email designers checking newsletter HTML for triggering spam filter rules
Not for
- Multi-channel SMS and push marketing journeys
Integrations
Spamcheck by Postmark alternatives
All 3 alternatives to Spamcheck by Postmark, compared Get the Toolvern badge for Spamcheck by Postmark
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Allegrow B2B sales email deliverability and spam risk monitoring platform Head to head: Spamcheck by Postmark vs GlockApps Spamcheck by Postmark vs Mailgun Optimize Spamcheck by Postmark vs Allegrow
Compiled by Stepan Noianov from the vendor's own site and pricing page. Something wrong? Report an inaccuracy.