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DMARC Checker

Check any domain's DMARC record. Inspect policy (none/quarantine/reject), pct, rua/ruf, sp, and alignment modes.

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

About this check

Inspect DMARC policy, alignment, and reporting addresses.

Frequently asked questions

What does the DMARC Checker actually check?
Inspect DMARC policy, alignment, and reporting addresses.
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.