Works with Mailgun
Spam Score Checker for Mailgun: Free Online Tool
→ Open the free Spam Score CheckerNo signup. 5 free checks a day. Works with any Mailgun campaign.
Mailgun's built-in tools cover the basics, but the spam score checker workflow often benefits from a dedicated check before sending. Pre-send spam-trigger analysis catches issues before they impact your sender reputation. Free rule-based scoring combined with a Naive Bayes classifier identifies precisely which content triggers fire.
Why pre-process before uploading to Mailgun
Mailgun does not offer pre-send rule scoring. External free tools fill this gap.
Step-by-step: spam-trigger analysis for Mailgun
- Paste your campaign HTML into the free SpamCipher spam score checker
- 60+ rules evaluate subject patterns, body keywords, header completeness, link density, HTML structure, image-to-text ratio, and authentication signals
- A Naive Bayes classifier trained on 50,000+ labeled messages provides a complementary spam-probability score
- Review the rule-by-rule breakdown and fix triggers before sending via Mailgun
Mailgun-specific deliverability quirks to know
Mailgun is API-first transactional + marketing. Pre-send hygiene scoring is essential since you control the HTML directly.
Frequently asked questions
Does Mailgun include a built-in spam score checker?
Mailgun provides basic functionality but lacks granular control. Mailgun does not offer pre-send rule scoring. External free tools fill this gap.
Is there a free way to spam-trigger analysis for Mailgun campaigns?
Yes. The free SpamCipher Spam Score Checker scores the HTML you paste against 60+ spam rules and an AI classifier, with no signup and 5 free checks a day. Fix what it flags, then send the campaign from Mailgun.
What image size limit does Mailgun enforce?
Mailgun accepts uploads up to 5000 KB per image and recommends a max width of 600px for email body width. Supported formats: JPG, PNG, GIF, WebP.
Does Mailgun verify SPF, DKIM, and DMARC automatically?
Mailgun requires SPF and DKIM via DNS. DMARC monitoring is available on their Foundation plan and higher.
What about subject line analysis for Mailgun?
Mailgun does not offer subject line analysis. External tools provide it. Use the free subject line analyzer for length scoring, spam-trigger detection, and sentiment analysis before pasting into Mailgun.
Related free tools
While preparing your Mailgun campaign, you may also want:
- Image Compressor — also free, browser-based, optimized for email marketers
- GIF Compressor — also free, browser-based, optimized for email marketers
- CSS Inliner — also free, browser-based, optimized for email marketers
- Inbox Preview — also free, browser-based, optimized for email marketers
Spam Score Checker also works with
