Email authentication checker
Check SPF, DKIM, DMARC, MX and BIMI records.
This check runs on the server. Input and results are not saved as execution history; hosted allowances apply.
About Email authentication checker
Inspect public SPF, DKIM, DMARC, MX and BIMI records with plain language configuration problems.
When to use it
Diagnose missing email authentication before testing a signup email.
Domain → SPF, DKIM, DMARC, MX and BIMI records and warningsHow to use it
- Enter a domain and, if known, its DKIM selector.
- Read the published records and diagnostic messages.
- Use the findings to review DNS with your mail provider.
Read the published mail configuration
SPF describes authorized sending infrastructure, DKIM publishes a selector specific signing key, and DMARC tells receivers how to handle alignment failures. MX describes incoming mail delivery. BIMI is an optional brand indicator. These records solve different problems; a missing BIMI record is not a mail authentication failure.
Enter the exact domain you want to check and ask your mail provider for its DKIM selector. The report distinguishes missing records, resolver errors and policies that only monitor mail. It does not send a message, verify a signature, expand every SPF include or look up inherited DMARC policies. Confirm the findings with your provider before editing DNS.
Limits & privacy
Public DNS only, ten seconds and up to 100 answers per query. DKIM requires a selector. This checks published syntax and common problems; it does not send mail, verify DKIM signatures, recursively evaluate SPF includes, or certify deliverability. BIMI is optional.
Use this tool from the API reference or connect through the SDK, CLI, SSH, or MCP. Hosted calls share your plan allowances.