Does Windows have a built-in PDF compare?
No. Microsoft Edge opens PDFs but cannot compare them, and there is no comparison feature in Windows 10 or Windows 11. You need a separate tool.
Option 1: a free browser-based comparison
Open the free PDF comparison tool in Edge, Chrome or Firefox. Drop the original PDF on the left and the revised PDF on the right and click Compare documents. The result is a change list with page numbers, a redlined PDF and a side-by-side view you can download. There is nothing to install, which matters on a work laptop where you cannot install software.
Documents up to 30 pages need no account, and files are discarded as soon as the comparison is returned.
Option 2: Microsoft Word
Word can open a PDF by converting it to an editable document, and Word has a Compare feature under Review, then Compare. In principle you can convert both PDFs and compare them. In practice the conversion changes line breaks, tables and spacing differently in each file, so Word reports many differences that are only conversion artefacts. It works best for short, simple text documents and when the originals were Word files in the first place.
Option 3: Adobe Acrobat Pro
Acrobat Pro includes a Compare Files tool. It is part of the paid Acrobat Pro subscription and is not in the free Acrobat Reader. If your organisation already licenses Acrobat Pro, it is a reasonable choice.
What to check in the result
- Every number, date and amount in a changed sentence.
- Deleted text, which is easier to miss than inserted text.
- Moved paragraphs, which some tools report as a deletion plus an insertion.
- Annexes and the last page, where late changes are often made.
Try it on your own documents. Upload two versions on the homepage. Documents up to 30 pages need no account, and nothing is stored.