See every addition, removal and edit between two PDF versions in seconds. Smart page alignment, ignore zones, OCR & AI Compare for scans and an AI summary of what changed — free, with no signup.
Three steps, no installs, no account. Built for contracts, invoices, listings, reports and any document that goes through revisions.
Add the original PDF as A and the revised PDF as B. Everything runs locally in your browser — nothing is uploaded.
Additions, removals and edits are highlighted word-by-word with a clickable change list, page heatmap and three view modes.
Download redline PDFs, a CSV change list, or a full comparison report — with an optional AI summary of what changed.
PDF Compare Pro reads the actual text layer of both documents, so the comparison survives reflowed paragraphs, font changes and re-exports.
Green for additions, red for removals, bright yellow for changes — every difference highlighted exactly where it sits on the page.
For tricky scans, photos and complex letterheads where plain OCR struggles, AI Compare reads both pages with Gemini Vision and pinpoints every change — right where it sits.
Inserted or deleted pages are re-paired automatically by content, so the rest of a contract or report stays perfectly comparable.
Drag a rectangle over headers, footers, dates or page numbers and that region is excluded from the comparison on every page.
Scans are detected automatically; the free built-in OCR converts them to text right in your browser for a proper word-level diff.
Every change is auto-tagged — amounts, dates, numbers, legal terms — and high-impact edits are flagged so you review what matters before signing.
Side-by-side with synced scrolling, an overlay with adjustable opacity, and a swipe divider for instant visual checks.
Redline PDFs of either version, a CSV change list for spreadsheets, and a complete comparison report ready to share.
Long revision? Get a plain-language overview of what actually changed — grouped into pricing & numbers, dates & deadlines, legal & liability, and more — plus risk flags a reviewer must verify before signing. Your files are never sent: the AI only sees the extracted change text. Available on Pro and Business plans — 4 credits per summary.
AI Summary — Pro & Business"The revised agreement raises the monthly fee from Rs 4,999 to Rs 5,499, moves the delivery deadline 15 days later, and removes the early-termination clause in section 4.2."
Most online PDF compare tools lock word-level comparison behind a paid plan and process your files on their servers.
| Feature | PDF Compare Pro | Typical online tools |
|---|---|---|
| Word-level text comparison | Free | Usually paid |
| Files stay on your device | Always | Uploaded to servers |
| Smart page alignment | Included | Rare |
| Ignore zones (headers, dates) | Included | Rare |
| OCR for scanned PDFs | Built-in | Extra cost |
| AI Compare for scans & photos | Pro plans | Not available |
| Redline + report + CSV export | Free | Varies |
| AI change summary | Pro plans | Not available |
Everything about comparing PDF documents with Tooljin.
Yes. Comparing, redline exports, CSV and the PDF report are completely free. The optional AI Change Summary is available on Pro and Business plans and uses 4 credits per summary.
No. Both PDFs are processed 100% inside your browser and never leave your device. The optional AI Summary sends only the extracted change text, never the files.
Yes. Scanned documents are detected automatically. Use the free built-in OCR (English) to convert scans to text, or switch on AI Compare (Pro) — which uses Gemini Vision to read both pages and pinpoint every change, even on complex letterheads, photos and multi-column scans where plain OCR struggles.
Smart page alignment re-pairs pages by content, so an inserted or deleted page does not break the comparison of the remaining pages.
Yes. Draw Ignore zones over any region — like headers, footers or page numbers — and those areas are excluded on every page.
Redline PDFs for both versions, a CSV change list, and a full comparison report PDF that can include the AI summary.
Each PDF can be up to 80 MB. Because processing happens on your device, very large documents depend on your browser's memory.
The built-in OCR currently supports English. PDFs with a real text layer compare in any language.
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Free, private, word-by-word — your documents never leave your browser.
Open PDF Compare Pro