Free Tools

Utilities for diagnosing and building email authentication records.

SPF Record Builder

Look up, understand, and build SPF records. Explains each mechanism in plain English.

Look up common selectors, validate DKIM records, and catch weak keys before they affect mail delivery.

Generate a 2048-bit DKIM keypair in the browser and copy the private key and DNS record separately.

DNS Record Checker

Check A, AAAA, MX, TXT, NS, SOA, CNAME, and PTR records against popular public resolvers.

Look up registrar details, dates, status, name servers, and raw WHOIS text for any domain.

DNS Propagation Checker

Check how a DNS record has propagated across 50+ global resolvers across all continents.

Domain Security Analyzer

Get an instant email security score for any domain. Checks DMARC, SPF, DKIM, BIMI, MTA-STS, TLS-RPT, and DNSSEC.

DMARC Record Checker

Look up and validate any domain's DMARC record. Inspects all tags and checks for common configuration errors.

DMARC Record Generator

Build a publish-ready DMARC DNS record. Choose your policy, report addresses, and forensic options.

DMARC Report Analyzer

Upload or paste a DMARC aggregate report (XML or ZIP) to decode and analyze your email authentication results.

Blacklist Checker

Check any domain or IP against 50+ real-time DNS blacklists. See where you're listed and get delisting guidance.

Email Header Analyzer

Instantly verify SPF, DKIM, and DMARC authentication, trace routing hops, and detect spoofing from any raw email header.

Verify DS and DNSKEY records, check registrar and nameserver signing status, and confirm DNS spoofing protection is active.