Mail-tester.com is useful for one-off email tests, but lacks API access, can't be automated, and requires sending an email each time. For developers who need programmatic checks, mailcheck is the better choice.
| Feature | mailcheck | mail-tester |
|---|---|---|
| Check Method | Domain-based (DNS) | Send email to test address |
| API Access | ✓ Free | ✗ No API |
| CI/CD Integration | ✓ curl/API | ✗ Manual only |
| No Email Sending | ✓ DNS-only | ✗ Must send email |
| Multiple Domains | ✓ Batch mode | ✗ One at a time |
| MTA-STS / BIMI | ✓ 7 checks | ⚠ Basic only |
curl https://korpo.pro/api/v1/check/yourdomain.com | jq .score