What are SPF, DKIM, and DMARC?

SPF, DKIM, and DMARC are email authentication systems that help receiving mail servers verify whether a message should be trusted. SPF checks which servers may send mail for a domain, DKIM verifies a signed message header, and DMARC tells receivers how to handle authentication failures.

These records reduce spoofing and phishing risk, but they only work when the domain's DNS entries are configured correctly and the sending service aligns with them.

Tool description

This tool checks the SPF, DKIM, and DMARC records for a domain and presents the results in separate tabs. It shows the raw DNS data, parsed tags, and warnings so you can spot configuration problems quickly.

It is useful when you are setting up a mail domain, troubleshooting delivery issues, or auditing email authentication settings.

Features

  • Record inspection: Reviews SPF, DKIM, and DMARC DNS entries in one place
  • Parsed details: Breaks down the tags and values so the records are easier to read
  • Warning summary: Highlights missing or suspicious settings that may affect delivery

How it works

The tool queries DNS for the selected domain, parses the returned records, and organizes the results by authentication type. DKIM lookup uses the selector you provide so you can inspect a specific signing key.

Limitations

  • DNS results can vary by resolver and may take time to propagate.
  • DKIM checks depend on the selector you enter.
  • Some domains publish partial or intentionally restrictive records, which can limit what the tool can display.