Free tools

Email tools that explain what they find.

Check how a message was delivered and whether a domain's SPF, DKIM and DMARC are set up properly. No sign-up, and nothing you check is stored.

Email header analyzer Paste raw headers to see the route a message took, the delay at each hop, and its SPF, DKIM and DMARC results. Runs in your browser. Open the tool → DMARC checker Look up a domain's DMARC record, read each tag in plain English, and see what to change before you move to quarantine or reject. Open the tool → SPF record checker Look up a domain's SPF record, follow every include, and count DNS lookups against the limit of 10. Open the tool → DKIM record lookup Check the DKIM public key for a selector, or try the selectors common providers use, and see the key type and size. Open the tool →

The header analyzer runs entirely in your browser. The DNS checkers query Cloudflare's public resolver straight from your browser over HTTPS, so Lettio's servers never see what you look up.

Lettio is private email on your own domain, hosted in the EU, with SPF, DKIM and DMARC set up for you. It is in a closed beta: request access.