See exactly what changed between two PDF versions — word-level diff, side by side, entirely in your browser. Both files are read on your device — nothing is uploaded, which matters for exactly the documents people compare.
Original (older version)
Drop your PDF files here
or
Up to 200MB on this device — processed in RAM, never uploaded
100% Local Processing
Zero Server Uploads
Changes missing from the new version show red here.
Revised (newer version)
Drop your PDF files here
or
Up to 200MB on this device — processed in RAM, never uploaded
100% Local Processing
Zero Server Uploads
New or changed text shows green here.
Comparison
MethodText diff · visual fallback for scans
Text rulesCase-sensitive · add/remove only
Scansbalanced sensitivity
ResultHighlights · overlay · TXT report · local
About Compare PDFs
Compare PDFs keeps the complete file workflow inside this browser tab. Your selected file, its name, contents, settings, and generated output are not sent to AntiUpload or a cloud conversion service. Ads and aggregate traffic analytics stay outside the processing boundary and receive no file object or working buffer.
Compare PDFs shows what changed between an original and a revised document without uploading confidential drafts. For text PDFs it extracts words, identifies additions and removals, and can distinguish text that moved to another position or page. Results are shown side by side with change counts and next/previous navigation.
Image-only or scanned PDFs automatically use pixel comparison so an empty text layer cannot produce a false “no differences” result. You can tune visual sensitivity, switch between side-by-side and overlay views, and drag the reveal control to inspect subtle layout or scan changes. The comparison is a local report; neither source file is modified.
How it works
Choose the original and revised PDFsThe two files stay in browser memory and are labeled clearly so their roles do not get reversed.
Pick comparison optionsEnable moved-text detection for edited drafts or adjust visual sensitivity when comparing scans and image-heavy pages.
Run the local comparisonAntiUpload uses word-level analysis for text documents and pixel-region analysis for scanned pages.
Review every changeUse counts, previous/next controls, side-by-side pages, or the overlay reveal slider to inspect the result.
When to use Compare PDFs
Review a revised contract
Find added clauses, removed wording, and paragraphs moved between pages without sending either confidential draft to a comparison service.
Check a regenerated report
Spot changed values, missing sections, pagination shifts, or formatting differences after exporting a new PDF.
Compare two scanned forms
Use pixel comparison and adjustable sensitivity when OCR text is absent or unreliable.
Frequently asked questions
Does PDF comparison upload either document?
No. Both PDFs are opened, rendered, and compared locally in your browser. Input files are read from browser memory and the output is created locally for your download. AntiUpload does not send file bytes, names, sizes, page counts, contents, passwords, or generated outputs through analytics or advertising requests.
Can it compare scanned PDFs?
Yes. When pages contain too little extractable text, the tool compares rendered pixels and highlights changed regions instead of reporting an empty text match.
What does moved-text detection do?
It distinguishes wording that was relocated from wording that was actually deleted and added. Enable it for contracts or reports where paragraphs often move during editing.
Does the tool create a merged or edited PDF?
No. It presents a visual comparison report and leaves both input files unchanged.
Compare PDFs keeps the complete file workflow inside this browser tab. Your selected file, its name, contents, settings, and generated output are not sent to AntiUpload or a cloud conversion service. Ads and aggregate traffic analytics stay outside the processing boundary and receive no file object or working buffer.
Compare PDFs shows what changed between an original and a revised document without uploading confidential drafts. For text PDFs it extracts words, identifies additions and removals, and can distinguish text that moved to another position or page. Results are shown side by side with change counts and next/previous navigation.
Image-only or scanned PDFs automatically use pixel comparison so an empty text layer cannot produce a false “no differences” result. You can tune visual sensitivity, switch between side-by-side and overlay views, and drag the reveal control to inspect subtle layout or scan changes. The comparison is a local report; neither source file is modified.
How it works
Choose the original and revised PDFsThe two files stay in browser memory and are labeled clearly so their roles do not get reversed.
Pick comparison optionsEnable moved-text detection for edited drafts or adjust visual sensitivity when comparing scans and image-heavy pages.
Run the local comparisonAntiUpload uses word-level analysis for text documents and pixel-region analysis for scanned pages.
Review every changeUse counts, previous/next controls, side-by-side pages, or the overlay reveal slider to inspect the result.
When to use Compare PDFs
Review a revised contract
Find added clauses, removed wording, and paragraphs moved between pages without sending either confidential draft to a comparison service.
Check a regenerated report
Spot changed values, missing sections, pagination shifts, or formatting differences after exporting a new PDF.
Compare two scanned forms
Use pixel comparison and adjustable sensitivity when OCR text is absent or unreliable.
Frequently asked questions
Does PDF comparison upload either document?
No. Both PDFs are opened, rendered, and compared locally in your browser. Input files are read from browser memory and the output is created locally for your download. AntiUpload does not send file bytes, names, sizes, page counts, contents, passwords, or generated outputs through analytics or advertising requests.
Can it compare scanned PDFs?
Yes. When pages contain too little extractable text, the tool compares rendered pixels and highlights changed regions instead of reporting an empty text match.
What does moved-text detection do?
It distinguishes wording that was relocated from wording that was actually deleted and added. Enable it for contracts or reports where paragraphs often move during editing.
Does the tool create a merged or edited PDF?
No. It presents a visual comparison report and leaves both input files unchanged.