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Email Tools Library

Each tool below helps you check one of the core deliverability components. They're lightweight, free, and require no login.

SPF Checker

Check if an SPF record is valid. Includes recursive lookup count.

SPF IP Checker

Check if an IP is authorized to send email for a domain. Includes recursive lookup count.

DKIM Validator

Validate DKIM records by domain and selector. Confirms existence and encryption strength.

DMARC Checker

Coming soon: validate your domain’s DMARC policy and reporting setup.

MTA-STS Checker

Check if your domain enforces secure transport (MTA-STS) for incoming email.

BIMI Validator

See if your domain has a valid BIMI record and logo setup.

PTR / Reverse DNS Lookup

Check if your sending IP has a valid reverse DNS record — critical for inbox delivery.

Mail Header Analyser

Paste an email header to trace routing, delays and spam filtering.

DNS Lookup Toolkit

Quickly check any DNS record type (A, TXT, MX, etc) across your domain setup.