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Email Subject Line Tester

Score a subject line for length, spam triggers, emoji, and personalization.

39 characters (60± recommended for mobile)

Spam risk score

79/100

Spam word hits

2

Emoji count

1

ALL-CAPS ratio

29%

Spam phrases detected

act now, limited time

Likely clean — deliverable without major spam flags.

Heuristic check only — inbox placement also depends on sender reputation, list quality, and the receiver's ESP spam rules. Always pair with a real spam-test tool before high-stakes sends.

About this tool

Paste a subject line (and optional preview text). Get a heuristic score, the word / character / mobile-visible length, word-level spam-flag hits (FREE, ACT NOW, $$$, etc), emoji count, ALL-CAPS check, and recommended tweaks. A local first pass before sending through a real ESP preview — answers the r/marketing 'will this go to spam' question.

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