Free PDF Compare
Upload two PDFs and see the text differences side by side. Green = added, red = removed, gray = unchanged. Download the report as HTML. 100% browser-based.
Compare Two PDFs Now
Drop the original on the left, the modified on the right. Click Compare. 100% in your browser.
Honest note
This tool compares text content only, not visual layout or images. If you move a paragraph, change a font, or swap an image, the text may be the same so the diff may show no changes.
Click or drop a PDF
Drag a file here, click to pick, or paste with Ctrl+V (Cmd+V on Mac).
Click or drop a PDF
Drag a file here, click to pick, or paste with Ctrl+V (Cmd+V on Mac).
The Best Free PDF Compare Tool
Side-by-side diff, color-coded lines, downloadable report. No signup, no watermark, no limits. 100% browser-based.
See Every Change
Upload two PDFs. The tool finds every line that was added, removed, or kept the same. A clean, easy-to-read list of changes.
Color-Coded Diff
Green = added lines. Red = removed lines. Gray = unchanged lines. Spot what changed at a glance, no reading every word twice.
100% Private
Both PDFs stay on your device. pdf.js extracts the text, a simple LCS diff finds the changes — all inside your browser. No uploads, no tracking.
Download Report
Click Download and get a single HTML file with the full diff report. Send it to a teammate, attach it to a ticket, or save it for your records.
Compare Two PDFs in 3 Steps
1. Upload Two PDFs
Drop the original in the left box and the modified in the right box. Both stay on your device. Either order works — green = added in the modified version.
2. Click Compare
The tool extracts text from every page of both PDFs using pdf.js, then runs a line-level LCS diff to find every added, removed, and unchanged line.
3. Read the Diff, Download
See the color-coded diff and the counts of added, removed, and unchanged lines. Click Download to save the full report as an HTML file.
Compare PDFs for Every Job
From contract edits to version compare — see every change at a glance.
Contract Edits
See exactly which lines your client or vendor changed in a contract. Spot added clauses, removed terms, or small word swaps before you sign.
Version Compare
Compare version 1 and version 2 of a report or proposal. See what was added, what was cut, and what stayed the same.
Legal Review
Lawyers and paralegals can compare two drafts of a brief or motion. Catch every change between revisions without reading line by line.
Audit Trails
See what changed between an old and a new policy, manual, or process document. Highlight every edit at a glance.
Pull-Request Style
Treat two PDFs like a pull request. The diff shows what was added (green) and what was removed (red) — same idea as git diff for code.
On the Go
Works on any phone, tablet, or laptop. Compare two PDFs right from your browser — no install, no app, no signup.
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Common Questions
Is the PDF compare tool free?
Yes. 100% free. No signup, no account, no watermark, no daily limit. Compare one pair of PDFs or a hundred — same free price forever.
How does the PDF compare tool work?
The tool loads both PDFs inside your browser using pdf.js. It extracts the text from every page in reading order. Then it runs a simple LCS (longest common subsequence) line diff between the original and the modified version. Added lines are shown in green, removed lines in red, and unchanged lines in gray. You can download the result as a single HTML file. Nothing is sent to a server.
Is my PDF uploaded to a server?
No. Your PDFs never leave your device. All text extraction and diffing happens inside your browser using pdf.js. There is no upload, no server copy, no tracking. 100% private.
Does the tool compare visual layout or images?
No. This tool compares text content only, not visual layout or images. If you move a paragraph, change a font, or swap an image, the text may be the same so the diff may show no changes. For a visual pixel-diff, use a dedicated image-compare tool on rendered page images.
What is LCS diff?
LCS stands for Longest Common Subsequence. It is a simple algorithm that finds the longest run of lines that are the same in both versions, then marks the rest as added or removed. The result is a clean, easy-to-read list of changes. It is the same idea used by most text-diff tools.
What happens if the two PDFs have different page counts?
The tool compares all the text from both PDFs. Lines that only appear in the longer PDF are shown as added (green). The tool shows the total count of added, removed, and unchanged lines so you can see at a glance how different the two files are.
Can I compare scanned PDFs?
No. Scanned PDFs are images, not text. This tool reads the text layer inside real PDFs. If a PDF is just photos of pages, the text layer is empty and the diff will be empty. Run an OCR tool first to add a text layer, then use this compare tool.
Will the diff match my exact words?
Usually yes. The tool rebuilds lines from the PDF text in reading order. If a PDF has unusual text spacing, very wide columns, or strange font metrics, two words on the same visual line may split into two diff lines. The result is still useful for spotting changes — it just may not be pixel-perfect.
Ready to Compare Two PDFs?
Free, no signup, no watermark. Side-by-side diff. Color-coded lines. Downloadable report. 100% browser-based.
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