# Free DMARC Checker

> Check whether a domain publishes a DMARC record and understand p=none, p=quarantine, p=reject, SPF, and DKIM alignment.

Canonical: https://sentryxmonitor.com/tools/dmarc-checker/
Last updated: 2026-08-08

Free read-only checker

A DMARC checker queries the TXT record at \_dmarc.yourdomain and evaluates whether the published policy can be parsed and used by receiving mail systems.

Only check domains you own or are authorized to assess. The scan is read-only and does not exploit systems.

## What does p=none mean?

p=none requests monitoring without asking receivers to quarantine or reject messages that fail DMARC. It is commonly used while collecting reports and correcting legitimate sender alignment.

## What do p=quarantine and p=reject mean?

These policies ask receivers to treat failing messages more strictly. Quarantine commonly routes them toward spam handling, while reject asks receivers not to accept them. Deployment should follow sender inventory and report review.

## How do SPF and DKIM relate to DMARC?

DMARC evaluates alignment between the visible From domain and an authenticated SPF or DKIM domain. Passing SPF or DKIM without alignment may not produce a DMARC pass.

## What happens after you submit?

The focused checker opens the full Sentryx outside-in report for the submitted domain. The same public scan backend can show related DNS, TLS, host, email-security, and header evidence so a narrow check can lead to a more complete ownership and monitoring decision.

## Continue learning

- [DNS Security and Monitoring Guide](https://sentryxmonitor.com/learn/dns/) - Learn DNS records, monitoring, DNSSEC, email authentication, TTL behavior, and how DNS changes affect security and availability.

- [DMARC, SPF, and DKIM Email Trust](https://blog.sentryxmonitor.com/dmarc-spf-dkim-email-trust/) - Understand how public email authentication records work together.

- [#dmarc](https://sentryxmonitor.com/glossary/#dmarc) - Related Sentryx Monitor guidance.

## Related
- [Home](https://sentryxmonitor.com/)