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📧 Email Auth Checker

Enter a domain to fetch MX, SPF, DMARC, MTA-STS, TLS-RPT records and validate them.

✅ 100% free, no signup

⚠️ Requests are made from DevLab servers. Private IP addresses and localhost are not allowed.

📚 Email Auth Basics

• SPF: Declares which IPs/hosts may send mail for this domain (TXT)

• DKIM: Adds a digital signature to messages — selector required so cannot be auto-detected

• DMARC: Policy on top of SPF/DKIM (none / quarantine / reject)

• MTA-STS: Tells senders TLS is required for delivery

• TLS-RPT: Where to send reports about TLS delivery failures

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