Free tool

Subject line checker

Test your email subject line against every major inbox client. See truncation at Gmail mobile, Apple Mail, Outlook, Yahoo. Flag spam triggers. Free, no sign-up.

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Emoji quick-insert
Truncation by client
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Gmail mobile 33
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Apple Mail mobile 41
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Outlook desktop 56
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Gmail desktop 70
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Yahoo / AOL 80
Inbox preview
Your brand
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Context

Every inbox client truncates long subject lines. Gmail mobile cuts at 33 characters. Apple Mail mobile at 41. Outlook desktop at 56. Gmail desktop at 70. Yahoo at 80. If your subject line runs past the limit, recipients see your message with the first 33 characters and nothing after that.

Why it matters

The subject line is the single highest-leverage piece of copy in your email. It decides whether recipients open or delete. Character-count matters because most opens happen on mobile, where real estate is tight. Spam words (free, guaranteed, 100%, winner, urgent) raise your risk of landing in the Promotions tab, or worse, the Spam folder.

More than a tool

This is one pre-flight check. Draftship runs 35 of them, live, in the editor.

Subject length, spam triggers, contrast ratios, Gmail clipping, alt text, undeclared variables, CAN-SPAM footers. All audited as you build. Open the editor and ship an email that passes every check.