Compare two PDF files

How to use Compare PDFs

1. Add both PDFsFirst the original (A), then the revised version (B). Swap with ↑ ↓.
2. CompareThe text of both files is extracted and diffed word by word.
3. Review changesRemoved words are red in A, added words are green in B. Download the HTML report.

How the comparison works

Text is extracted from every page of both documents and compared with a word-level difference algorithm. The result shows A on the left with deletions struck through, and B on the right with insertions highlighted, with page markers so you can find each change in the original files. Counts of added and removed words give a quick sense of scale.

Scans and images

Comparison works on text. If one of the PDFs is a scan, run OCR PDF on it first; OCR errors may then show up as small changes, so read flagged words in context. Pure layout changes (moved images, new fonts) are not reported.

Typical uses

Contract redlines when the counterparty didn’t track changes, checking a revised quote, verifying that a re-exported report kept its wording, or reviewing policy updates between yearly editions.

Reading the report

The report shows both versions side by side. Removed words are struck through in the left column and added words are highlighted in the right column, so a changed number in a contract or a reworded clause jumps out. Unchanged passages are kept for context. If whole paragraphs moved, they appear as one removal and one addition rather than a move.