Check your domain's email security setup in seconds. Diagnose SPF, DKIM, DMARC, and ARC issues before they land your emails in spam.
Get a 0–100 grade for any domain's email security. Checks DMARC, SPF, MX, and DKIM records with actionable recommendations to improve your score.
Check your score →Will your emails reach the inbox? Checks authentication, blacklist status, and forwarding readiness with a deliverability prediction score.
Test deliverability →Look up any domain's DMARC record. See the policy, alignment settings, and reporting config with actionable recommendations.
Check DMARC →Validate your SPF record, count DNS lookups against the 10-lookup limit, and analyze every mechanism in the record.
Validate SPF →Look up DKIM records by selector. Verify key type, size, and configuration for any domain.
Check DKIM →View MX records, identify your email provider, and check mail server priority and configuration.
Lookup MX →Paste raw email headers for a human-readable breakdown of authentication results, routing hops, and delivery timing.
Analyze Headers →Paste email headers to cryptographically validate ARC seals. The only free online ARC chain validator.
Validate ARC →Email authentication (SPF, DKIM, DMARC, and ARC) protects your domain from being spoofed and ensures your legitimate emails land in the inbox instead of spam. Without proper authentication:
Use these free tools to check your current setup and identify issues. If you're forwarding email and seeing DMARC failures, ARC-Relay can fix that automatically with ARC sealing and SRS rewriting.