Compare two PDF or text files

How to use

1. Choose the old version in the first box and the new version in the second box, or drop the files onto them. PDF files and text files (.txt, .tex, source code…) are supported.
2. Click “Compare”. The comparison runs in your browser and nothing is uploaded.
3. Text removed from the old version is highlighted in red, and text added in the new version is highlighted in green.
4. Use “Next change” and “Previous change”, or the n and p keys, to jump to the next or previous change. Both documents scroll to the matching place.
5. Keep “Synchronized scrolling” checked to scroll both documents together. Use the + and − buttons above each document, or Ctrl and the mouse wheel, to zoom; with “Synchronized zoom” checked, both documents zoom together.

Good to know

• For PDF files, the comparison is made on the text, word by word. Changes to images, layout or colors are not detected, and scanned PDFs without selectable text cannot be compared.
• A paragraph that was moved appears as removed in one place and added in another.
• For text files, the comparison is made line by line, and the changed words are highlighted inside modified lines.
• Both files must be of the same kind: two PDF files, or two text files.