What it does
mail-tester.com provides a sample-message spam check alongside SPF, DKIM, DMARC and other mail-domain utilities.
Use a sample sent from the newsletter or email system you are investigating, then open the report for its generated testing address. mail-tester analyzes that message, its mail server and sending IP. The free allowance is three tests within the last 24 hours. Free results remain accessible for 7 days; an account with your own prefix extends that to 30 days. Anyone who knows the testing address can access its result during that period. Sending another message to the same address immediately deletes and replaces the previous test. Its reversed SpamAssassin score is useful diagnostic context, but other filters can judge the message differently. Extra test packs and iframe/JSON API access have paid terms.
Strengths
- Sample-message checking workflow
- Related mail-domain utilities
Watch out for
- Message assessment requires sending a sample to the service
Sources
- Newsletters spam test by mail-tester.com (Oct 26, 2026)
- mail-tester testing and result visibility FAQ (Oct 26, 2026)