Text Diff
Compare two texts and highlight the differences. Runs on your device — nothing is uploaded, nothing is stored.
Paste an original text on the left and a changed version on the right, and this tool marks what differs. Below the two boxes the changed version is listed line by line: lines that were removed are shown in red with a minus sign, lines that were added are shown in green with a plus sign, and lines that match are left plain. The original text is shown beside it for reference.
A Copy Patch button copies the same result as plain text, with each line starting with +, - or a space. It is a quick way to see which lines of a note, config file, list or paragraph were edited.
Why this runs on your device
Both texts are compared by code running in your browser tab, and nothing is sent to a server. That matters when you are comparing a config file with credentials in it, a draft contract or two versions of private notes.
- Paste the original text into the left box.
- Paste the modified text into the right box.
- Read the comparison below: red with a minus is removed, green with a plus is added.
- Press Copy Patch to copy the result as plain text.
- This is a simple line-by-line comparison, not a true diff. Line 1 is compared with line 1, line 2 with line 2, and so on by position. If you insert or delete a line near the top, every line after it is shown as changed even though only one line moved. For code or documents where lines get inserted, expect noisy results.
- A changed line is shown as a whole: the old line in red and the new line in green. It does not highlight which words or characters changed inside the line.
- The copied patch is only the list of prefixed lines. It has no file headers or line-number hunks, so tools such as git apply or patch cannot use it.
- Whitespace and capitalisation count as differences, and there are no options to ignore them. Blank lines that match are not marked, and an empty line that replaces text shows as a removal only.