Compare PDFs
Compare text differences between two PDF files and highlight changes.
Original PDF (A)
Drop original here
Modified PDF (B)
Drop modified here
How to Compare PDF Files
1. Drag and drop or select your original PDF file into the "Original PDF (A)" upload zone.
2. Upload the corrected or modified PDF file into the "Modified PDF (B)" upload zone.
3. Click "Compare PDFs" to parse the document text layers directly inside your browser.
4. Inspect side-by-side differences showing deletions highlighted in red and additions in green.
FAQ
Q. Can I compare two scanned PDFs or flat image files?
No. This tool parses selectable text layers directly. It does not support comparing scanned image PDFs where character metadata is missing.
Q. How are the text differences visually highlighted?
Deleted texts are highlighted in red (with a strikethrough) on the PDF A side, while newly appended texts are highlighted in green on the PDF B side. You can instantly trace differences in a side-by-side layout.
Q. Does the tool compare layout alignments or graphical shifts?
No. This utility is strictly dedicated to comparing text information. It does not inspect layout visual alignments, background color tints, or graphic modifications.
Q. Is there any privacy risk of leaking my confidential documents?
None. Comparison algorithms run completely inside your local browser memory via client-side JavaScript. Document files never touch our servers, protecting your privacy.
Q. Can I compare password-secured PDF documents?
No. Secure files cannot be parsed directly. Please use our Unlock tool to strip security first, then upload.
Q. Does the comparison work for other languages besides Japanese and English?
Yes. We compare characters based on Unicode formatting. Text files in Japanese, English, Chinese, European languages, etc. will be compared accurately.
Q. Is there an account requirement or charge?
No. The platform requires no registration, signup, or subscriptions, and it is 100% free.
Q. What is the maximum file size?
The maximum allowable PDF file size is 100MB per document.
Q. Can I inspect comparison diffs on mobile devices?
Yes. Our responsive layout allows inspecting comparison panels side-by-side or scrollable on mobile platforms (iOS and Android).
Q. Will my original files be modified or overwritten?
No. The uploaded files are read-only. The platform processes the comparisons in memory without updating your local documents.