How to compare two PDF files and find the changes in a contract
The other party sends the contract back “with minor corrections”. Reading both versions line by line takes an hour and it is easy to miss something. An automatic comparison does it for you.
Why compare document versions
Changing a single number in an amount, a deadline or a contractual penalty can have serious consequences, and in a document of a dozen pages it is very easy to miss. The same goes for terms and conditions, offers, specifications or a thesis after the supervisor’s corrections. A comparison shows all the differences at once, so you can focus on assessing the changes rather than hunting for them.
How to compare PDFs in PDFowo
- Open the Compare PDF tool.
- Upload the older version of the document in the left box and the newer one in the right box.
- Go through the list of changes: each item shows what was removed, what was added and on which page.
- Click “Next” and “Previous” to move between the changes. In the page preview, removed text is highlighted in red in version 1 and added text in green in version 2.
The comparison works word by word across the whole document, so it detects a change even when an added paragraph has pushed the rest of the text onto the next page. Both files are processed in your browser and are not uploaded to a server, which matters for confidential contracts.
Text or page appearance
- “Text” mode works for documents with a text layer, i.e. exported from Word or another system. It shows the exact words that changed.
- “Page appearance” mode compares the pages as images. It helps with scans, technical drawings and graphic designs, or when you want to catch a change in a stamp, signature or logo.
If the differences come only from capital letters or punctuation, tick “Ignore case and punctuation” so the list shows only the meaningful changes.
A report with the changes
You can also download a PDF report: version 1 with the removed text marked in red and version 2 with the added text marked in green. Such a file is easy to send to a lawyer or attach to your correspondence with the other party.
Free, no sign-up. Your files stay on your device.
Open the Compare PDF tool →Example: an amendment to a rental agreement
The landlord sends a new version of the agreement and says they “only changed the dates”. You upload the old and the new version and immediately see three changes: a new date, a higher rent and an added paragraph about the deposit. Instead of reading the whole document, you know exactly what to ask about before signing.
Frequently asked questions
Does the comparison work on scanned documents?
Yes, in “Page appearance” mode, which compares the pages visually. “Text” mode needs a text layer, so for scans the tool switches to the visual comparison automatically.
Are my contracts uploaded anywhere?
No. Both files are read and compared in your browser.
How many pages can be compared?
The tool compares up to 100 pages of each document.
Can I download the comparison result?
Viewing the differences is free. You can also download a PDF report with the changes highlighted.