TEXT vs TEXT · Local tool
Compare Text
Find what changed between two texts, down to the words inside a line.
Last updated
How do I find the differences between two pieces of text?
Paste the original into filetity's left box and the changed version into the right, and the differences appear side by side, with nothing uploaded. It uses Myers' algorithm in linear space, so a block inserted in the middle is recognised as an insertion rather than making everything after it look changed, which is the failure that makes a naive line-by-line comparison useless. Inside a line that changed, the words are compared again and only the parts that moved are highlighted, so a paragraph with one different word shows you that word. Windows and Mac line endings are never reported as a difference, nor is a trailing newline. Case, leading and trailing spaces, and blank lines can each be ignored with a toggle.
01 / Your device
the file stays here
02 / Browser memory
the work runs locally
03 / Back to you
saved on this device
When you would use this
Situations, not settings.
- Two versions of a document from different people
- The changed words are highlighted inside the line, so you can see what was actually edited rather than that a paragraph moved.
- Checking a contract or a policy against the last draft
- Neither text is uploaded, which is the part that matters when the document is under negotiation.
- Two config files where one machine works and the other does not
- Line endings and trailing newlines are never reported, so the real differences are not buried under whitespace noise.
How it works / no cloud
A conversion engine, not an upload form.
The comparison uses Myers' algorithm in linear space, so an inserted block is recognised as an insertion rather than making every line after it look changed. Inside a line that changed, the words are compared again, so a paragraph with one different word shows that word rather than the whole paragraph.
- Offline ready
- Installable app
- No file limit queue
Straight answers
No accordion. Nothing hidden.
- Is it free?
- Yes, with no watermark and no page limit.
- Does it need an account?
- No. There is no account system.
- Is my file processed on my device?
- Yes. The file is read by your browser and never uploaded. There is no server to send it to.
- What formats are supported?
- Any two pieces of text. Prose, code, CSV, logs and configuration all work the same way.
- What are the limits?
- Up to 50,000 lines a side. Two texts sharing thousands of lines in a very different order are refused with a suggestion, because that case costs far more than its size suggests.
- Does it work on mobile?
- Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
- Does it work offline?
- Yes, once the page has loaded. The tool keeps working with no network connection.
- Why does it show changed words instead of just changed lines?
- Because a line diff on a paragraph tells you almost nothing. When two lines are similar enough to be a modification of one another, the words are compared as well and only the parts that moved are highlighted. Lines that share less than half their characters are treated as one removal and one unrelated addition instead, which is the honest description of what happened.
- Do Windows and Mac line endings count as differences?
- No. A file saved with CRLF endings and the same file saved with LF endings compare as identical, and so does a file with a trailing newline against one without. Those differences are real but they are never what somebody is looking for, and reporting them buries the ones that are.
- Why was my comparison refused when the files are not that big?
- Because the cost of a diff is not the size of the input. Two files sharing thousands of identical lines in a shuffled order are the expensive case, and it can take several seconds where a much larger file with a few edits takes milliseconds. Sorting both sides and comparing again usually answers the question you actually had.
- What do the ignore options actually do?
- Ignore case compares letters without regard to capitals. Ignore edge spaces strips leading and trailing whitespace before comparing, which is what you want when an editor has reindented a file. Ignore blank lines skips empty lines entirely, and the line numbers still refer to the original text so the gutter stays useful.
- Can it compare two files rather than pasted text?
- Paste is the input here. Open both files, copy each into a box, and compare. Keeping it to paste means the tool works identically for a snippet out of a chat, a block from a terminal and the contents of a file, which is most of what people are comparing.
Keep working locally
3 available · more coming