Free email tools
Inspect email infrastructure without guesswork
Run focused checks against public DNS or analyze content locally in your browser. Every tool distinguishes observed data from errors and unknown outcomes.
Email cost calculator
Compare Resend, SendGrid, Mailgun, Postmark, MailerSend, Mailtrap and SendHQ costs for your monthly email volume, with plans and overage rates.
Open toolEmail DNS checker
Email domain tester: check public SPF, DKIM, DMARC, and MX records through two DNS-over-HTTPS resolvers, with disagreement and lookup-error states.
Open toolBIMI checker
Look up a BIMI record and its DMARC prerequisite without claiming that a logo or certificate will be accepted by every mailbox provider.
Open toolEmail preflight checker
Analyze email HTML, plain text, links, accessibility, and common client-safety risks locally in your browser before sending a test.
Open toolBounce diagnostics
Interpret SMTP and enhanced status codes deterministically while keeping permanent, temporary, and unknown outcomes distinct.
Open toolEmail checker
Check an email address for syntax errors, look up the domain MX records via two DNS resolvers, and see if it is a free or disposable provider.
Open toolSPF checker
Look up the SPF TXT record for a sending domain through two public resolvers, with the mechanism list, visible lookup budget, and disagreement states.
Open toolWhat these tools can establish
They can show public DNS answers, parse published policies, flag common free and disposable mailbox domains, inspect HTML markup, and classify server response codes. Resolver names and error states remain visible.
What they cannot establish
They cannot prove an address exists, promise delivery or inbox placement, validate every email client, or guarantee that a mailbox provider will display a BIMI logo.
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