DMARC Record Parser — Check & Validate

A free edge API by formatho.com, privacy-first developer tools.

Free, no signup, runs entirely in your browser — your data never leaves your device.

🔓 Free🔒 Zero tracking🚫 No data collection⚡ Edge-fast

Usage — validate a record

curl "https://dmarc-parser-formatho.filesformatho.workers.dev/api?record=v%3DDMARC1%3B%20p%3Dreject%3B%20rua%3Dmailto%3Admarc%40example.com"

Every tag is checked against RFC 7489: required p, valid policies, pct range, URI limits (max 2, 1024 chars each), alignment modes, duplicate tags, unknown tags — each with a plain-English explanation.

Usage — look up a domain's live record

curl "https://dmarc-parser-formatho.filesformatho.workers.dev/api?domain=gmail.com"

Fetches the _dmarc.gmail.com TXT record over DNS (Cloudflare DoH) and validates it. Multiple DMARC records are flagged — receivers reject those.

Common mistakes it catches

Missing p= (policy) or v=DMARC1 not first
rua with more than 2 URIs or oversized URIs (must be ≤1024 bytes)
pct outside 0–100, non-numeric ri, invalid adkim/aspf modes
fo=0 combined with 1/d/s, duplicate tags, stray quotes from zone-file pastes

Full parameter reference: /api endpoint.

Privacy-first: parsing runs in-memory at the edge; domain lookups resolve via public DNS only, nothing you send is logged or stored.

Full browser tool

Check DMARC entirely client-side: DMARC Parser on formatho.com.

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