Free Tool

Email Subject Line Tester

Analyze your email subject lines for sentiment, readability, spam risk, and engagement potential. Powered by NLP and SpamAssassin-derived rules.

Test your subject line

Type or paste your email subject line to test it.

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SpaceCRM

Your subject line here...

--/100

Type a subject line to see analysis

A score of 70+ is considered good. Aim for 80+ for optimal open rates.

Keep subject lines under 60 characters for mobile optimization. 41-60 characters is the sweet spot.

Words like FREE, ACT NOW, LIMITED TIME, and excessive punctuation (!!!) can trigger spam filters.

SpaceCRM helps you send better emails, faster.