How to Remove Zero-Width Characters From a String

Zero-width characters inside a string cause bugs that are invisible in your editor: failed comparisons, broken parsing, and mismatched keys. Here is how to strip them.

Which characters to target

The common zero-width and invisible characters:

• U+200B zero-width space
• U+200C zero-width non-joiner
• U+200D zero-width joiner
• U+2060 word joiner
• U+FEFF byte-order mark / zero-width no-break space

In JavaScript

A single regex replace removes them:

const clean = str.replace(/[\u200B-\u200D\u2060\uFEFF]/g, '');

If you need to keep the zero-width joiner for emoji, exclude \u200D from the range and handle it separately.

In Python

import re
clean = re.sub(r'[\u200b\u200c\u200d\u2060\ufeff]', '', s)

Or, to strip a broader set of invisible and format characters, remove characters in the Unicode "Cf" (format) category:

import unicodedata
clean = ''.join(c for c in s if unicodedata.category(c) != 'Cf')

That is a heavier hammer, so use it when you want to remove all format characters, not just the zero-width ones.

For a one-off, use a cleaner

If you just have a string to fix and do not want to write code, paste it into a cleaner that strips invisible characters by code point. textscrubr removes zero-width spaces, joiners, the word joiner, and the byte-order mark, shows you a count of what it found, and keeps the joiners that emoji, Persian and Indic text need, so it does not break them.

Verify

After stripping, compare the length before and after, or re-scan for the code points. If the count drops and a re-scan finds nothing, the string is clean. Adding this step to input handling or a data pipeline stops zero-width characters from ever reaching comparisons and parsers.