How do I compare two texts and see what changed?
Paste the original text and the new version into FixDoks's Text Compare tool and click Compare. It highlights removed lines in red, added lines in green, and marks the exact words that changed inside each line, using the same diff method as Git. Switch between side by side and unified views, entirely in your browser.
Text Compare (Diff Checker) at a glance
| Input | Two texts to compare |
|---|---|
| Output | Line and word level differences, side by side or unified |
| Processing | In your browser; your files are not uploaded |
| Price | Free |
| Works on | Chrome, Edge, Safari and Firefox on Windows, Mac, Android and iPhone |
How to use Text Compare and Diff Checker
- Paste the original text in the left box and the changed text in the right box.
- Optional: tick Ignore case or Ignore extra spaces.
- Click Compare text. Removed text is red, added text is green, and changed words are highlighted inside each line.
- Switch between Side by side and Unified views.
See what changed between two versions
A contract came back with edits but no tracked changes. A teacher returned your essay and you want to see exactly what was corrected. Two versions of a config file behave differently. In each case you need to know what changed, and reading both versions side by side is slow and error prone. This diff checker compares them for you and highlights every difference.
How the comparison works
FixDoks first compares the texts line by line using the Myers diff algorithm, the same approach used by Git and most programming tools. It finds the smallest set of lines that were added or removed to turn the original into the new version. When a removed line and an added line sit in the same place, they are shown as one changed line, and a second pass compares the words inside it so you can see the exact word, number or punctuation mark that differs.
- Red lines were removed from the original.
- Green lines were added in the new version.
- Inside changed lines, struck-through red words were deleted and green words were inserted.
- Line numbers on each side help you find the spot in your own file.
Ignore options
Ignore case treats "Total" and "total" as equal, useful when only capitalisation was tidied up. Ignore extra spaces treats any run of spaces or tabs as a single space and ignores spaces at the ends of lines, which hides reformatting noise when comparing code or text copied from different programs.
Side by side or unified
Side by side puts the original on the left and the new version on the right, which is easiest for prose and contracts. Unified view lists everything in one column with minus and plus markers, the format developers know from Git. On a phone, unified view is easier to read.
What people compare
- Two drafts of an essay, article or statement of purpose.
- A rental agreement or offer letter before and after the other side's edits.
- Two exports of a list, to spot which emails or product codes are new.
- Code snippets, JSON and config files. For JSON, run both through the JSON formatter first so the layout matches and only real changes show.
Limits
The comparison runs in your browser, so confidential documents never leave your computer. Texts of tens of thousands of lines compare in about a second. If two very long texts are almost completely different, the tool shows them as fully replaced rather than searching for small matches, to avoid freezing your browser. For Word or PDF files, copy the text out of the document and paste it here.