Text Compare
Runs in your browserCompare two blocks of text and see exactly what was added, removed or changed.
Original
Changed
What is a Text Compare?
A diff finds the smallest set of line insertions and deletions that turns one text into another, then shows you just that — not the whole document, only what changed. It's the same idea behind `git diff` or a document's "track changes" view, applied to any two blocks of text you paste in directly.
This comparison works line by line: a line counts as unchanged only if it matches exactly, so a single edited word inside a long line shows the whole line as removed-and-re-added rather than highlighting just that word. That's the standard behaviour for comparing config files, code, or structured lists, where line-level changes are what you actually care about.
How to use it
- Paste the original text into the left panel and the changed version into the right.
- The diff generates automatically below — removed lines are marked in red, added lines in green.
- Check the summary count of lines added and removed at a glance.
Example
A small edit
Original: "The quick brown fox"
Changed: "The quick red fox"− The quick brown fox
+ The quick red foxFrequently asked questions
Does this highlight individual word changes within a line?
No — the comparison works at the line level, which is the standard granularity for comparing config files, code, and lists. A line with even a single character changed shows as one removed line and one added line, rather than highlighting the specific word that differs.
Why do my identical-looking lines show as different?
The most common cause is invisible whitespace — a trailing space, a tab instead of spaces, or different line endings (\r\n vs \n) from copying out of different programs. Since the comparison is exact, any of these will register as a change even though the visible text looks the same.
Is there a size limit?
The comparison algorithm's cost grows with the square of the line count, so very large documents — tens of thousands of lines — can become slow to diff in the browser. For typical use (comparing paragraphs, config files, or a few hundred lines of code) it's instant.
Can I compare two files instead of pasting text?
Not directly in this version — paste the contents of each file into the two panels. Most text editors and IDEs let you copy a whole file's contents in one action.