Free email authentication tools

Check how a domain is set up for email authentication, and get the exact records to publish to fix problems.

• SPF checker

  Check an SPF record for errors, count its DNS lookups against the limit of 10 and see every include.

• DMARC checker and generator

  Check a DMARC record, see what each tag means and whether report addresses are authorised, or build a new record.

Lookups run in your browser using Cloudflare public DNS; the domains you check are not sent to ZeroDMARC.