Free tools
Email deliverability tools — all free, no signup
Quick, focused tools for diagnosing email auth and validating addresses. They run in your browser, hit DNS directly, and don't store anything.
SPF Checker
Most popularLook up and validate any domain's Sender Policy Framework record.
Open tool →DMARC Checker
Verify your DMARC policy, coverage, and report destinations.
Open tool →DKIM Checker
Look up DKIM by selector — or auto-scan 10 common selectors.
Open tool →Email Validator
Check syntax + MX + disposable in one shot. Browser-only.
Open tool →More than one-off checks?
BounceBlocker validates emails in bulk, continuously monitors blacklists, and tests where your mail actually lands across Gmail, Outlook, and Yahoo.
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