Compare PDFs
Put two versions of a document side by side and get a page-by-page report of every text change.
Compare PDFs online, free and private
When two versions of a contract, report or manuscript land in your inbox, the question is always the same: what actually changed? Reading both side by side is slow and error-prone — a single altered number or deleted clause is easy to miss. A PDF comparison does the reading for you and reports every added and removed line.
PDFToolz extracts the text of both documents page by page, diffs them line by line, and produces a clean HTML report with removals in red and additions in green. The comparison runs entirely in your browser, so confidential drafts and contracts are never uploaded anywhere.
How to compare pdfs in your browser
- 1
Add two PDFs
Select or drop both versions of the document. Put the older version first and the newer one second — the report labels them Old and New, and you can drag to reorder them before comparing.
- 2
Run the comparison
Press ‘Compare files’. The text of each page is extracted and reconstructed into lines, then the two documents are diffed page by page.
- 3
Read the report
Download the HTML report and open it in any browser. Each changed page gets its own section: lines removed from the old version are marked in red with a minus, lines added in the new version in green with a plus.
Why use PDFToolz for this
Line-level text diff
Text runs are grouped back into visual lines using their position on the page, then compared with the same longest-common-subsequence algorithm used by code diff tools — so the report shows real, readable changes rather than raw text fragments.
A report you can share
The result is a self-contained HTML file with the change summary and every difference highlighted. Send it to a colleague or archive it with the documents — no special software needed to open it.
Confidential drafts stay private
Contracts and unpublished drafts are exactly the documents you don't want on a third-party server. Both files are read and compared locally in your browser; nothing is transmitted.
Free with no limits
Compare as many document pairs as you like — no account, no watermark, no page limits.