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📬 SPF & DMARC Record Builder and Checker

📬 SPF & DMARC Record Builder and Checker

Check the syntax of an SPF or DMARC DNS record you paste, count SPF DNS lookups, or build a new record. Works offline: nothing is looked up or sent.

1 · Check a record

Paste a record starting with v=spf1 or v=DMARC1.

    2 · Build a record

    What this can and cannot see. It checks the text you paste against the SPF (RFC 7208) and DMARC (RFC 7489) syntax. It does not query DNS, so it cannot follow include: chains, see whether the record is actually published, or test DKIM. Lookups inside included records also count towards SPF's limit of 10. Change live DNS carefully and start DMARC at p=none with reports.

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