Outlook subject (web)
Outlook · WebYour brandLast chance: 30% off everything ends tonight at…midnight9:41
Outlook · Web · Subject line
Outlook subject (web) length checker (~52 characters)
About 51 characters at a 1400px-wide window. Modeled as a pixel box calibrated to the character count seen on the device, so wide and narrow letters are handled.
Gets cut
The Outlook subject (web) limit at a glance
- Limit
- about 52 characters (351px)
- How it’s counted
- By rendered width in the system font at 14px — wide letters use more room.
- What happens when it’s too long
- Cut on screen with “…”
- Where the number comes from
- Measured on devices
How to write for it
- B2B audiences read in Outlook — check this one for work emails.
FAQ
Outlook subject (web): questions
What is the Outlook subject (web) limit?
About 52 characters (351px). About 51 characters at a 1400px-wide window. Modeled as a pixel box calibrated to the character count seen on the device, so wide and narrow letters are handled.
What happens if my subject line is too long?
Outlook · Web still shows it, but cuts it with “…” — anything past the cut is invisible to most people.
Why does the character count change?
This screen cuts by width, not characters. Wide letters like W and M use up to four times the room of i or l, so two texts of the same length can be cut in different places.
Can I check many at once?
Yes — upload a CSV or Excel file on the Bulk page and Truncly checks and fixes every row, then gives the file back with fixes added.