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DKIM Checker

Look up a DKIM public key by selector and domain. Check key length, algorithm, and record syntax. Free and instant.

This tool is being wired up. The analyzer ships in the next build phase.

About this check

Look up DKIM public keys by selector and validate them.

Frequently asked questions

What does the DKIM Checker actually check?
Look up DKIM public keys by selector and validate them.
Is this really free?
Yes. Every on.bo tool is free, no signup required, no rate-limit tricks.
Do you store the data I check?
We log minimal metadata to keep the service healthy. Lookups themselves are not retained beyond short-term caching.