Type a subject line, then hit test. Everything runs in your browser, nothing is sent anywhere.
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Most phones cut subject lines after about 35 characters. What survives the cut is what gets opened.
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Get a Free ConsultationFrequently asked questions
What makes a good email subject line?
The best subject lines are 41 to 50 characters, specific, and free of spam-trigger words like FREE or GUARANTEED. A number or a question adds curiosity, and the first 35 characters should carry the message alone since phones cut the rest.
Why did my email go to spam?
Common causes are trigger words (free, urgent, act now, limited time), all-caps words, and multiple exclamation marks. Run your subject line through this tester to spot them, and keep your sending list clean with confirmed opt-ins.
Is this email subject line tester free?
Yes, 100% free with no signup and no limits. It runs entirely in your browser, so your subject lines never leave your device.
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