Subject Line Length Checker

Preview how Gmail, Outlook, and Apple Mail truncate your subject on mobile.

How it works

See if your subject gets cut off on phones

Type a subject → click Check length → see how Gmail, Outlook, and Apple Mail roughly truncate it on mobile and desktop. Limits are educational estimates.

Or start from a real-life example

Results appear here after you click Check length.

Ready to send with MailShrine?

New accounts get free signup credits. Fix the copy, then send from MailShrine.