Is 15 to 50 characters a Gmail or Outlook limit?
No. It is an editorial preview range used by this checker. It is not a published cutoff from a mailbox provider.
Available now
Email subject line tester
Check length, shouting, and a short editorial word list before you send.
Not sure what to enter? Start with a complete example.Fill the form in one click, run it as-is, or edit the example into your own business.
The subject you would send. Blank text is rejected.
Runs locally
Example output
Sample, not a prediction: "Your workflow review is the next step" is 37 graphemes, inside the editorial 15 to 50 range, with no list match and no extra exclamation mark. The email subject line tester says it is usable as a test. A Chinese character is about twice as wide as a Latin letter, and the band does not switch by language. That does not predict the open rate.
How to use it
- Paste the subject you would actually send.
- Read the character count and whether it sits inside 15 to 50.
- Read any list matches, all-caps flag, and extra exclamation marks.
- When the verdict suggests a rewrite, consider changing the subject before it enters the sequence.
FAQ
Does a word-list match mean the email will be blocked?
No. The list is fixed and short: free, winner, guarantee, urgent, congratulations, plus three Chinese phrases. A match means those words are present.
Why is there no score?
The result is a suggestion: usable as a test, or consider a rewrite before sending. It is not a number out of 100 and it does not predict opens.
Sources
- Unicode Standard Annex #29: grapheme clusters The count uses grapheme clusters. The 15 to 50 band and the word list are editorial and are not in this annex.
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