Line ending and whitespace inspector

Open a file or paste text to see its line endings, indentation, BOM and any invisible characters, then normalize it with one click.

🔒 Runs entirely in your browser. Nothing you paste is uploaded or sent to a server.

Paste text, or open a file to check its real line endings and encoding

Open a file

Visible whitespace (→ tab, · trailing space, ␍␊ CRLF, ␊ LF, red = invisible or unusual character)

Normalize

Line endings Tabs → spaces Remove BOM Strip trailing whitespace NBSP → space Remove zero-width Straighten smart quotes Single final newline

Why invisible characters break things

Problem	Typical error	Fix
CRLF line endings in a shell script	`/bin/bash^M: bad interpreter`, `exec user process caused: no such file or directory` in Docker	Convert to LF (bad interpreter)
Mixed CRLF / LF	Git warning `LF will be replaced by CRLF`, noisy diffs	Pick one and set `.gitattributes` (LF will be replaced by CRLF)
Tabs and spaces mixed	Python `TabError: inconsistent use of tabs and spaces`, YAML "found character that cannot start any token"	Convert tabs to spaces (TabError)
UTF-8 BOM	`Unexpected token` in JSON, `#!` line ignored, PHP "headers already sent"	Remove the BOM
Non-breaking space (U+00A0)	`SyntaxError: invalid non-printable character`, "command not found" for a pasted command	Replace with a normal space
Zero-width space (U+200B)	A variable or key that "exists" but is never found	Remove it
Smart quotes `“ ”`	Syntax errors in code copied from documents or chat	Straighten them

Pasting vs opening a file

Browsers convert every pasted line break to LF, so the line-ending count is only reliable when you open the file with the button above. Opening a file also reports its encoding (UTF-8, UTF-8 with BOM, UTF-16, or not valid UTF-8). The file is read locally and never uploaded; Download result saves the normalized version with the original name.

Doing it from the command line

file script.sh                      # "with CRLF line terminators"
cat -A script.sh | head             # ^M$ = CRLF, ^I = tab, M-BM-  = NBSP
sed -i 's/\r$//' script.sh          # CRLF -> LF (or: dos2unix script.sh)
sed -i 's/[ \t]*$//' file           # strip trailing whitespace
sed -i '1s/^\xEF\xBB\xBF//' file    # remove a UTF-8 BOM
expand -t 4 in.py > out.py          # tabs -> 4 spaces
grep -nP '[\x{00A0}\x{200B}]' file  # find NBSP and zero-width spaces

To stop the problem coming back, add * text=auto eol=lf to .gitattributes and an .editorconfig with end_of_line = lf and indent_style = space.

Last updated 2026-11-05.