How to find what changed between two versions of a PDF
Last updated 26 September 2026
Reading a long contract twice to find the changes is how people end up agreeing to a clause they never saw. A comparison does it in seconds and misses nothing in the words.
Compare the two versions
- Open Compare PDFs.
- Drop the old version first, then the new one. The first is marked Before, the second After.
- Press Compare them.
- Skip the pages marked unchanged. Under each changed page, read the Was and Now lines.
Read a change in its place
To see a change with the text around it, open the new version in Open a PDF, press Ctrl+F and search for a few words of the changed line.
What to look for in a contract
Numbers first: prices, dates, notice periods, percentages. A change from 30 days to 60 days is one word. Then short words with big effects: "may" becoming "must", "and" becoming "or", a "not" added or taken away. Then whole new paragraphs, which the comparison lists as lines that were put in.
What is not compared
Only the words are compared, not the look: bold, colour, pictures or layout changes are not shown. And a scan has no words in it at all. If one or both versions are scans, run them through OCR a scan first, then compare the copies it saves.