Paste your subject and email body. Get a 0-10 spam score with rule-by-rule breakdown - same kind of analysis SpamAssassin runs, in your browser, instantly.
This tool scores email content against 60+ heuristics inspired by SpamAssassin and modern mailbox-provider filters. Paste a subject line and body (HTML or plain text); the analyzer returns a 0-10 spam score plus a rule-by-rule breakdown showing exactly what tripped each rule and how many points it added.
Scoring is content-only - we don't check your sender reputation, IP blacklists, or DNS authentication (use our other tools for those). The output isolates the ONE variable you fully control before hitting send: the words and HTML in your message.
Content scoring is half the inbox-placement story. These factors matter equally and are checked separately:
Our complete sender-reputation guide covers content, authentication, list hygiene, and the metrics that actually move inbox placement.
Read the sender-reputation guideContent is one of three big inputs. The other two are sender reputation (your IP/domain history) and authentication (SPF/DKIM/DMARC alignment). A clean content score is necessary but not sufficient. If you've ruled out content, check your IP against our blacklist checker and your auth records against the SPF/DKIM/DMARC tools.
No. Trigger words like "free" or "limited time" are common in legitimate marketing - they only become a problem in combination with other signals (ALL CAPS, shorteners, missing unsubscribe). Focus on the high-severity findings; small +0.2/+0.3 hits are usually fine if your overall score stays under 2.5.
Presence of unsubscribe/opt-out language is a positive signal - it's a CAN-SPAM/RFC 8058 requirement for bulk mail and indicates legitimate marketing. We subtract 0.5 from the score to reward it. Missing unsubscribe in a long HTML email adds 1.0 to the score.
Similar idea, different approach. mail-tester requires you to send a real email to a unique address; it then runs full SpamAssassin + checks your auth + IP reputation. Our tool is content-only and instant - paste-and-score, no email send needed. Use our tool for fast content iteration; use mail-tester for the final pre-flight including the auth/reputation pieces.
Single-email checks, no signup required
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