Compare PDF
Choose an original and a revised PDF. PDFboat lists the words that were added, removed or changed, and marks the places on every page that look different. Both files stay in your browser and are never uploaded.
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Original
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Revised
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What to compare
How to compare two PDF files and see what changed
- Choose the original PDF and the revised PDF.
- Pick what to compare: words and appearance, words only, or appearance only.
- Click Compare. Read the changes in the side-by-side view with a draggable divider, or download the comparison PDF with the differences marked.
Questions
What does it compare?
The words: paragraph by paragraph, then word by word inside paragraphs that changed. And the look: each page of the revised file is laid over the same page of the original and the places that differ are boxed. You can choose either one or both.
Will it work for scanned PDFs?
The look comparison does. Scans have no text, so the words cannot be compared unless you first run OCR PDF on both files.
Why does it say every page looks different?
If a word was added early on, everything after it moves, so every later page looks different. The text list shows what really changed. Use "Words only" for such files.
Do the two files need the same page size?
No. The revised page is stretched to the size of the original before the look is compared, so small size changes still line up.
How do I read the side-by-side view?
The original is on the left and the revised file on the right, with a divider you can drag (or move with the arrow keys; double-click resets it to the middle). Scrolling one side scrolls the other. "Next difference" and "Previous difference" jump between the marked places, and clicking a text change jumps to its page. "Only pages with differences" hides the rest.
What is in the comparison PDF?
A summary page, then every page that looks different with the original and the revised side by side and the changes marked (coral on the original, blue on the revised).
Can I compare password-protected files?
Remove the password first with Unlock PDF, then compare.
Are my files uploaded?
No. Both files are read and compared inside your browser tab.