Guide
This free email deliverability checker verifies the three DNS records that decide whether your mail reaches the inbox — SPF, DMARC, and DKIM — from a single input: the email address you send from. You don't need to know which domain to query or what a DKIM selector is; the tool works that out for you.
How to check your email deliverability
- Paste the email address you send from (e.g.
[email protected]). The domain after the @ is what gets checked, and it is shown before you run anything. - Click "Check all three". SPF and DMARC are looked up directly; for DKIM, common provider selectors are scanned automatically.
- Read the three result cards. Each shows OK / needs review / problem, the raw record, and the specific issues found — with a link to the dedicated checker for the full breakdown.
What each record does
| Record | What it proves | Typical failure |
|---|---|---|
| SPF | The sending server is on your allowed list | Too many DNS lookups (over 10), +all, multiple records |
| DKIM | The message was signed by you and not altered | Revoked (empty) key, weak 1024-bit RSA, wrong selector |
| DMARC | Tells receivers what to do when SPF/DKIM fail | No record, p=none left on forever, no report address |
Example
Pasting [email protected] checks yourcompany.co.jp: the SPF card might show a healthy record using 4 of 10 lookups, the DMARC card might warn that p=none is monitoring only, and the DKIM card might find the google selector with a 2048-bit key — telling you exactly which of the three needs work.
When to use the dedicated checkers
The one-shot view is for triage. For fixing, open the linked tool: the SPF checker expands every include with the lookup count, the DMARC checker explains every tag, and the DKIM checker lets you enter a custom selector when the automatic scan finds nothing.
Limitations
- The DKIM scan covers common provider selectors only; a custom selector must be entered in the dedicated DKIM checker.
- The tool checks published DNS records, not live mail flow — passing checks are necessary for inbox placement, not a guarantee of it.
