5 tools
Compare PDF
Find what changed between two revisions.
Comparing documents can be done two ways, and they answer different questions. A text diff tells you which words were added, removed or altered — precise, but blind to layout. A visual diff renders both pages and highlights differing pixels, which catches moved images and restyled type but flags harmless reflow too. Running whichever matches your question, rather than assuming one diff fits all, is what makes comparison useful.
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Compare PDF Text
Only the words, so a reformatted document still reads as unchanged.
PDF Text Diff
Diff semantics applied to PDF text, at word granularity.
Visual PDF Comparison
Compare what the page looks like, not just what it says.
Highlight PDF Differences
A shareable PDF with the changed regions marked on the page.
About compare PDF
Should I use text or visual comparison?
Use text comparison for wording changes in a contract or report. Use visual comparison when layout, images or styling matter, or when the files are scans with no text layer.
Why does visual comparison flag an entire page?
A change early on can reflow everything after it, so every subsequent line sits at a new position and differs pixel-wise. Text comparison is the better tool in that situation.