Byte counter, one text or a whole column
Paste text to see its size in UTF-8 bytes, or drop a spreadsheet to check every row against a byte limit. Rows that go over are listed with the part that won't fit.
Count one text
0 / 255 bytes0 characters (spaces and line breaks included)
Check a whole column
Drop an Excel or CSV file with one entry per row. Rows over the limit are listed with the part that won't fit.
or drop it here · xlsx · csv
The file is read in this browser only. It is never uploaded.
Choose several files at once to collect every over-limit row into one spreadsheet (Pass).
Questions
How are bytes counted?
As UTF-8: ASCII letters, digits and spaces are 1 byte, accented Latin letters are 2, Korean, Chinese and Japanese characters are 3, and emoji are 4. A line break is 1 byte, or 2 if you turn on Windows line breaks (CRLF).
Can I check a whole column at once?
Yes. Drop an .xlsx or .csv file, pick the text column, and set the limit. Every row over the limit is listed with how many bytes it is over and the text that won't fit. You can save the file with three columns added: bytes, bytes over, and the cut-off text.
What is the NEIS rule?
NEIS is the system Korean schools use for student records. Its 2026 guide counts a Korean character as 3 bytes and a letter, digit or line break as 1. Pick "NEIS" to use that rule; it also counts symbols as 3 bytes so text never ends up over the limit.
Is my text uploaded?
No. Text and files are read in this browser tab only and are gone when you close it.