I am currently using \StrLen{#1} inside my \newcommand. This works flawlessly for any common string written in latin alphabet.

"Hello" has string length of 5 for example. Problem is with chinese characters. String length of "容容" is 8 which is technically corrent, but I wasn't able to find multibyte alternative to StrLen which would return 2.

Note: I am using pdflatex.

Regards, Jan

  • Welcome to TeX.SX! Please help us help you and add a minimal working example (MWE) that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass{...} and ending with \end{document}.
    – Skillmon
    Commented Mar 8, 2018 at 22:46
  • if you used luatex or xetex then each unicode character would be a single token otherwise you need to count character tokens ignoring any above hex 80 and less than hex C0 Commented Mar 8, 2018 at 22:50
  • Can you please show how and why you're using \StrLen?
    – egreg
    Commented Mar 8, 2018 at 23:34

2 Answers 2


You can count the utf-8 start bytes so for example

enter image description here


\ifx\relax#2 \the\numexpr#1\relax
  \the\numexpr(#1+\ifnum\expandafter`\string#2<"80 1\else \ifnum\expandafter`\string#2>"BF 1 \else 0 \fi\fi




  • This is exactly the solution I need. Tested and it works! Commented Mar 9, 2018 at 12:58
  • Note that this gives codepoints, not graphemes. These will be the same on PDFTeX (which does not support combining characters), but not necessarily in LuaTeX or XeTeX.
    – Davislor
    Commented Dec 10, 2020 at 21:29
  • @Davislor true although that is what (some) definitions of string length for a unicode string would expect. Commented Dec 10, 2020 at 22:02

Just for the sake of variety, here's a LuaLaTeX-based solution.

enter image description here

\zz{Hello}, \zz{容容}, \zz{¢Àïα}

If your TeX distribution is quite old (say, at least 4 years old as of late-2020), simply replace utf8.len with unicode.utf8.len to get the code to run.

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