SPF, DKIM & DMARC Checker by imisofts

Check SPF, DKIM, DMARC and MX in one click, and see whether a new record has propagated. Plain-English fixes.

Find out in one click why your email might land in spam, and what to change. Type a domain or paste an email address, and each of its essential records gets a clear Pass, Check or Fix, with what was found shown underneath. Every problem comes with a plain-English "How to fix" note and a link to a free step-by-step guide. SPF - Finds the record, and flags a second one - Catches syntax errors, such as a misspelled mechanism or an invalid IP range - Counts lookups against the limit of 10 in RFC 7208 - Catches include: and redirect= terms that point to a name with no sender policy - Spots terms after "all", which receivers ignore - Warns about +all, ?all and the outdated ptr mechanism DKIM - Looks for keys on 28 common selectors, or your own - Reads a selector straight from a pasted DKIM-Signature header - Reads the exact key size, and flags damaged, revoked and too-short keys DMARC - Reads your policy: none, quarantine or reject - Spots report addresses (rua) that are not complete mailto: addresses - Explains pct= when only part of failing mail gets the policy - Falls back to the parent domain's policy when a subdomain has none, including sp= MX - Lists mail servers in priority order, and flags a null MX - Flags Google Workspace or Microsoft 365 missing from SPF EXTRAS - Shows whether BIMI and MTA-STS are published PROPAGATION The Propagation tab asks six public DNS providers at once whether a record you just added or changed has reached them. Type the value you expect, and the list shows exactly which ones have it. - Shows how long each provider keeps an old answer before it looks again - Explains a cached "not found", and tells you where the domain's DNS is hosted - Spots Cloudflare's proxy (orange cloud) on link-tracking hostnames, and a CNAME at the root of a domain - Keep checking repeats every 30 seconds in its own tab and stops once all six have it - A checklist tests up to 30 new entries in one go SHARE THE RESULTS Copy report puts the results on your clipboard, ready to send to whoever manages your DNS. PRIVATE BY DESIGN - No sign-up, no account and no permissions to grant - Lookups go straight to public DNS providers over HTTPS - imisofts receives no data, and your recent lookups stay in your browser Want it done for you? imisofts sets up email authentication and sending infrastructure for B2B teams: https://imisofts.com/email-infrastructure This tool works from public data only. It cannot see how a specific inbox provider treats your mail. Google Workspace is a trademark of Google LLC and Microsoft 365 is a trademark of Microsoft Corporation. We are not affiliated with Google, Microsoft or Cloudflare.