Free online tool that analyzes a sent email’s content, spam score, SPF/DKIM and server/DNS configuration, producing a diagnostic report with issues and pass/fail checks.

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Mail Tester provides a fast, technical check of an email message and its sending setup to help identify deliverability and spam-related issues. Send an email to the unique test address shown on the site and Mail Tester analyzes the message content, server configuration, DNS records and sending IP to produce a readable report with a spam score and diagnostic details. Key capabilities: - Spam scoring and content analysis using established filters to highlight elements that increase spam risk. - Automated checks of authentication records (SPF, DKIM) and common DNS/mx configuration errors that affect delivery. - Sender/IP reputation and basic header inspection to show how receiving servers may evaluate the message. - Clear, itemized report that flags problems and shows which checks passed versus failed, making technical issues easier to prioritize. - Rapid, one-shot testing workflow that requires only sending a single message to the provided test address to receive results. Benefits: - Helps diagnose why emails land in spam or are rejected by recipients’ servers by combining message and infrastructure checks. - Useful for developers, deliverability engineers, and marketers who need a quick verification of authentication and basic server setup. - Saves time compared with manual inspection of headers and DNS records by consolidating common deliverability tests into a single report. - Produces actionable findings suitable for troubleshooting or handing to an IT/admin to resolve configuration problems. Relevant keywords incorporated naturally for search optimization: email deliverability test, spam score checker, SPF DKIM test, mail server diagnostics, sender reputation check, email header analysis. The description focuses on factual capabilities and diagnostics rather than promotional claims; Mail Tester functions as a targeted technical tool for assessing message spam risk and mail server configuration.

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