Compare text
Paste the original text and the modified one. Removed lines are marked in red, added lines in green, and inside modified lines the words that changed are highlighted.
You can also drag in a .txt, .md, .csv, .json, or .html file. It is not uploaded to any server.
You can also drag in a .txt, .md, .csv, .json, or .html file. It is not uploaded to any server.
What to compare
Differences
Type or paste two texts to compare them.
Shortcuts: N next difference, P previous.
How to use it
- Paste the original text on the left and the modified text on the right, or open two text files.
- Choose how much detail you want (whole line, words, or characters) and whether to ignore case, accents, spaces, or blank lines.
- Read the summary, the similarity percentage, and the differences. Use Next and Previous, or the N and P keys, to step through them.
- Download the differences as a .diff file or as an HTML page, or copy the patch.
Frequently asked questions
How do I see what changed between two versions of a text?
Paste the old version into “Original text” and the new one into “Modified text.” Removed lines show in red with a minus sign, added lines in green with a plus sign, and in modified lines the words that changed are underlined or struck through. You do not depend on color alone: every type has its own symbol.
What does the similarity percentage mean?
It is the share of the text that stays the same: twice the number of characters in common divided by the total characters in both texts. If there is even one difference, it never reaches 100%.
Can I ignore case, accents, or spaces?
Yes. With the options on, “HELLO” and “hello” count as equal, and so do “naïve” and “naive,” double spaces, or extra blank lines. The summary tells you when the texts are identical only because of those options.
What is a .diff file?
It is the standard patch format used by Git and other tools: it lists removed lines with “-” and added lines with “+”, with three lines of context. It only includes the differences you see with the options you chose.
Does it work with large files?
Yes. With texts of several megabytes the comparison runs in the background so the page does not freeze, and only the first differences are drawn until you ask for more.
Is my text sent to a server?
No. The comparison happens in your browser and your texts never leave your device.
How texts are compared
First the tool finds the lines that appear in both texts, in the same order, using the Myers algorithm, the same one Git uses. What is left over in the original is marked as removed, and what is left over in the modified text is marked as added. When a line changed a little, it is paired with its new version and only the words, or characters, that differ are highlighted.
What it is for
- Reviewing versions: see what changed in a contract, an article, or a paper between two drafts.
- Configurations and lists: compare two text, CSV, or JSON files.
- Edits: see exactly what someone else changed in your text.
Tips
If you compare text pasted from different programs and everything shows as changed, turn on “Ignore extra whitespace”: it is the most common cause. If the line breaks differ a lot, try the Text cleaner first.
Updated on September 30, 2026