Compare PDF Online Free
Upload two versions of a PDF and instantly see every difference highlighted — added text in green, removed text in red, changed text in yellow. Perfect for contracts, reports, and legal documents.
AOriginal / Old Version
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BRevised / New Version
Drop revised PDF here
or click to browse
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Comparing PDFs…
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Comparison Complete
Differences detected between the two documents.
12
Words added
7
Words removed
3
Pages changed
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Page-level diff · Image comparison · Change history export
How It Works
Find every difference between two PDFs in seconds
Upload Both PDFs
Upload your original PDF as File A and the revised version as File B. Both files are processed in parallel for speed.
Automatic Diff
Our engine extracts and compares text word by word across every page. Image regions are compared pixel-by-pixel.
Download Diff Report
Download a color-coded PDF report showing every addition, deletion, and change highlighted on the original pages.
Comparison Features
Precise word-level difference detection
Word-Level Text Diff
Every added, removed, or changed word is individually highlighted in color. Changes within the same sentence are pinpointed exactly.
Image Comparison
Images that were added, removed, or replaced are flagged with a colored border. Pixel-level changes within existing images are highlighted.
Page-by-Page Summary
A summary at the top of the report shows how many words were added, removed, and changed per page, so you can jump straight to the most-changed sections.
Side-by-Side View
Pro users get a side-by-side PDF viewer showing both versions simultaneously with synchronized scrolling and linked change highlights.
Formatting Detection
Detect font, size, bold, italic, and color changes even when the text wording is identical — essential for style guide compliance checks.
100% Private & Secure
Both files are encrypted in transit, processed in isolated containers, and deleted within 24 hours. We never read or retain your documents.
Frequently Asked Questions
Yes. If File B has more pages than File A, the extra pages are shown as "added" in the diff report. If it has fewer, the missing pages are shown as "removed". Each page pair is aligned as best as possible by content similarity.
Yes. Scanned PDFs are automatically processed through OCR before comparison, so text is extracted and compared accurately even from image-only documents. For best results, run OCR on both files first using our OCR PDF tool.
The report is a PDF with all changes highlighted in color directly on the page — green for added text, red for deleted text, and amber for changed text. A summary section shows total added, removed, and changed words per page.