Online text diff: compare two texts or files
Paste two versions of a text, or open two files, and see exactly what changed. The text diff lines them up side by side, marks lines that exist on only one side, and highlights the words or characters that changed inside a line, so a one-word edit or an extra blank line in a long file stands out at once.
Features
- Side by side: Left and Right are aligned line by line with line numbers, with blank space where a line exists on only one side.
- Colour coded: red is only in Left, green is only in Right, amber is different on both sides.
- Changes within a line: only the words or characters that differ are highlighted.
- Invisible changes made visible: changed spaces show as
·and tabs as→; different line endings (CRLF vs LF) in opened files and a missing final newline are reported. - Ignore whitespace and ignore case when they do not matter.
- Files: open a file or drop one onto either side.
- Fast: large files with a few changes compare almost instantly.
- Private by design: no uploads, no tracking, nothing stored.
How to compare text
- Paste or drop the first text into Left and the second into Right.
- Press Compare, or Ctrl/⌘ + Enter. Dropped and opened files compare automatically.
- Jump between differences with Prev/Next, or press p and n.
- Turn on Only show differences to collapse unchanged parts of large files.
- Press f or the maximize button next to Next to give the comparison the whole window; Esc restores it.
Frequently asked questions
Are CRLF and LF line endings treated as different?
No. Lines are compared without their line endings, so a Windows file and a Unix file with the same lines are identical. The summary notes when two opened or dropped files use different line endings (pasted text always arrives with LF line endings), or when one side has no newline at the end.
What does Ignore whitespace do?
It ignores spaces and tabs at the start and end of each line and treats any run of whitespace as a single space. Whitespace between words is not removed, so a b and ab are still different.
How can I see whitespace changes?
Inside a highlighted change, spaces are shown as · and tabs as →, so a trailing space or a tab replaced by spaces is visible.
Are my files uploaded?
No. Pasted text and opened files are read and compared in your browser. Nothing is sent to a server or stored.