Email Subject Line Tester
Score your subject line before you hit send. Check for spam words, length, and mobile preview.
Your subject line is the single biggest factor in whether your email gets opened or ignored. A great product or offer means nothing if recipients delete your email before reading it.
This tool analyzes your subject line in real time: checking for known spam trigger words that cause email clients to flag your message, detecting all-caps and excessive punctuation, showing a mobile inbox preview (truncated at ~40 characters), and giving you an overall score from 0 to 100 so you can iterate fast.
0 characters
Type your subject line above to see the analysis.
Frequently Asked Questions
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