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Security tool · Free

DNS & email health check.

Review the public records that help your website resolve and protect your email from spoofing. Nothing is stored.

Microsoft 365 commonly uses selector1 and selector2. Other providers use different selectors.

What we check

Four signals that matter.

MXMail routing

Identifies the services authorised to receive mail for your domain.

SPFSender policy

Lists systems permitted to send email using your domain.

DMARCProtection policy

Defines how receivers handle mail that fails authentication.

DKIMMessage signing

Verifies cryptographic signatures when a selector is supplied.