How to Compare Two PDF Files
Diff versions and spot changes in 3 simple steps.
Upload Both PDF Versions
Drop your original version (A) and revised version (B) into the comparison boxes above.
Deep Text & Layout Diffing
Our engine scans word-for-word and highlights deleted text in red and new text in green.
Inspect Synchronized Pages
Scroll through synchronized pages with color-coded highlights and inspect the exact change logs.
The Best Online PDF Diff Tool
Synchronized scroll locking, red/green highlighted text diffing, exact change counts, and side-by-side viewport alignment.
Synchronized Lockstep Scrolling
Scroll both versions together in lockstep to immediately identify paragraph shifts and layout revisions.
Color-Coded Visual Highlighting
Highlights deleted text in red-tinted bounding boxes and newly added words in crisp green highlights.
Detailed Change Counter
Get instant metrics on total added words, deleted phrases, and modified page numbers across versions.
100% Free with No Accounts
Compare unlimited document revisions with zero monthly subscriptions or paywalls.
Private & Auto-Deleted
All transmissions are encrypted via SSL/TLS. Files are processed securely and deleted immediately after your session.
Cross-Platform Diffing
Compare PDF documents smoothly in any modern web browser on Mac, Windows, Linux, and iPad.
Synchronized Diffing & Character-Level Matching
PDF Maya performs deep tokenization to highlight modified phrasing without getting thrown off by formatting adjustments.
Word & Character Tokenization
Detects added words, deleted sentences, and altered numbers with pinpoint bounding-box highlighting.
Lockstep Synchronized Scroll
Both document panels scroll together automatically, keeping matching clauses perfectly aligned side by side.
Layout & Table Shift Detection
Identifies moved paragraphs, reordered tables, and newly added figures across complex multi-page documents.
Exportable Summary Metrics
View a complete statistical breakdown of total modifications, added phrases, and deleted terms between revisions.
Practical PDF Comparison Use Cases
Verify legal revisions, audit balance sheets, and review manuscript proofs with confidence.
Contract Revisions & Redlines
Verify that counter-party attorneys didn't sneak in unauthorized clauses or alter payment schedules in agreements.
Book Manuscripts & Proofs
Check author draft submissions against final typeset proof copies to ensure copyediting fidelity.
Financial Audits & 10-K Filings
Compare quarterly balance sheets and SEC filings to verify disclosures and numbers between quarters.
Academic Papers & Dissertation Drafts
Track changes between faculty review notes and final thesis revisions with clear line-by-line diffs.
Your Documents Stay Private & Secure
We prioritize document confidentiality and data privacy across all comparison operations.
256-Bit SSL/TLS
All transmissions are secured with end-to-end HTTPS encryption.
Instant File Deletion
Uploaded PDFs and comparison logs are purged automatically from memory.
No Account Needed
Compare unlimited files without registration, emails, or paywalls.
Universal Support
Works seamlessly in any browser on macOS, Windows, iOS, and Android.
Frequently Asked Questions
Everything you need to know about comparing PDF documents online.
How do I compare two PDF files for free?
What do the different highlight colors mean?
Do the pages scroll together?
Can I compare documents with different page counts?
Are my confidential legal contracts secure?
Do I need desktop software like Adobe Acrobat DC to compare PDFs?
Explore More PDF Tools
Everything you need to convert, organize, and edit documents in one place.
PDF to Word
Convert PDFs into editable Microsoft Word documents.
Edit PDF
Add text, annotations, and shapes directly to PDFs.
Sign PDF
Add verifiable signatures to contracts and forms.
Merge PDF
Combine multiple PDFs into a single file.
Protect PDF
Encrypt PDF files with AES passwords.
Compress PDF
Reduce PDF file size without quality loss.