Free Online Compare PDF
Upload two PDFs to see differences highlighted — text changes, added/removed pages — 100% private in your browser.
Compare PDF
Upload two versions of a PDF (original & revised). We'll extract text and show a simple diff of changes.
No file selected
No file selected
How to Compare Two PDFs Online for Free in 2026
Need to spot changes between document versions? Whether it's contracts, reports, legal files, or academic papers — our free tool compares two PDFs by extracting text and showing a clear diff (added, removed, or changed content).
Powered by pdf-lib and simple text comparison — everything runs locally in your browser. No files are uploaded, ensuring complete privacy.
Key Features
- Side-by-Side Upload: Compare any two PDFs easily.
- Text Diff Highlighting: Green for added, red for removed/changed text.
- Page-Aware Comparison: Detects added/removed pages (basic level).
- 100% Private: No server processing — your documents stay on your device.
- No Limits: Free, unlimited comparisons, no registration.
Common Use Cases
Lawyers reviewing contract revisions, editors tracking document changes, students comparing thesis versions, businesses auditing reports, anyone needing to verify updates without expensive software.
Frequently Asked Questions
Is this PDF comparison tool free?
Yes. Completely free, no signup, no limits, no watermarks.
Are my PDFs safe and private?
Yes. All comparison happens in your browser — nothing is sent to any server.
What kind of differences does it detect?
It compares extracted text line-by-line: added lines (green), removed/changed (red/strikethrough). Page count differences are noted. Visual/layout changes (images, fonts) are not highlighted yet.
Can I download a visual diff PDF?
Current version shows text diff. Generating a full visual comparison PDF (side-by-side or overlay) is more complex — planned for future updates!