Mail Tester
Enter a domain to run its MX, SPF, DMARC, and DKIM checks together and see a combined pass/fail report.
Overview
A domain's email setup depends on several independent DNS records: MX records so mail has somewhere to go, SPF and DMARC so receiving servers can judge whether a message is legitimately from that domain, and DKIM so individual messages can be cryptographically verified. Checking each with a separate tool works, but it's easy to miss one. This tool runs all four checks in a single pass and reports each result plainly, so you can see the full picture at once.
Examples
A domain with mail authentication fully configured
example.com
✓ MX records — 2 mail server(s) found. ✓ SPF record — v=spf1 include:_spf.example.com ~all ✓ DMARC record — v=DMARC1; p=reject ✓ DKIM record (selector: google) — found
How It Works
- Enter a domain name, e.g. example.com.
- Optionally enter a DKIM selector if you know it — DKIM is skipped (not failed) if left blank, since there's no single selector every domain uses.
- Click Run Test to check MX, SPF, DMARC, and (if a selector was given) DKIM together.
- Review the pass/fail report for each check.
Use Cases
Pre-launch mail-authentication checklist
Confirm MX, SPF, DMARC, and DKIM are all correctly published before pointing a new domain's outbound mail at production.
Quick diagnosis of deliverability complaints
Get a fast overview of which authentication mechanism is missing when a domain's mail is landing in spam.
Tips
- DKIM is the one check this tool can't run without your help — it needs the selector, which isn't discoverable from DNS alone. Check your email provider's DKIM documentation if you don't know it.
- For a deeper look at any one check, use the dedicated tool for it — MX Lookup, SPF Checker, DMARC Checker, or DKIM Checker each show more detail than fits in this combined report.
FAQ
DKIM records are published under a selector the domain's mail provider chooses, and there's no way to discover it purely from DNS. If you don't enter one, that check is skipped rather than reported as a failure, since a missing selector isn't itself a misconfiguration.
No. Each check calls the same public lookup endpoints used by the individual MX Lookup, SPF Checker, DMARC Checker, and DKIM Checker tools, and nothing about the request is stored beyond their normal short-lived caching.
Website Health Score covers a broader mix (DNS, SSL, SPF, DMARC, security headers) and rolls them into a single 0-100 score. Mail Tester is narrower and mail-specific — MX, SPF, DMARC, and DKIM — reported as a plain pass/fail checklist rather than a weighted score.