Compare Two PDFs and Highlight Differences

A vendor sends a “final” contract, then sends a revised version two days later with no redline and no change summary. Reading both copies side by side is slow and error-prone—a swapped number on page 14 or a deleted clause on page 7 can slip past even a careful reader. Loading both files here flags every text, layout, and metadata difference so you know exactly what moved.

When a Side-by-Side Check Actually Matters

Contracts after negotiation rounds, insurance policies at renewal, grant proposals after reviewer feedback, and regulatory filings across years are the four cases where a compare catches things a human eye skips. Any time someone says “nothing changed” but a signature is still required, run a compare first.

Visual Diffs vs Text Diffs: Which One to Trust

Text mode extracts the character data from each page and compares strings. It catches word changes, added paragraphs, and deleted sentences. It misses anything that is not text—moved logos, resized charts, or shifted margins.

Visual mode renders each page as an image and overlays the two versions. It catches every pixel-level shift, including layout changes that text mode ignores. The trade-off is that it flags trivial rendering differences (a font hinted slightly differently across PDF readers) as changes. Use text mode for contracts. Use visual mode for design proofs or scanned documents where text extraction is unreliable.

Do This First

1. Load the “before” PDF on the left and the “after” PDF on the right.
2. Pick text compare for contracts and legal documents, visual compare for anything with images or complex layouts.
3. Review the highlighted differences page by page.
4. Download the comparison report if you need a record of what changed.

Scanned Pages, OCR, and What “No Change” Really Means

• Scanned PDFs. A scanned page is an image, not text. Text mode cannot extract characters from it, so the compare will come back empty even if the content differs. Use visual mode for scans, or run OCR on both files first.
• Metadata-only edits. Someone can change the author field, the creation date, or the PDF title without touching the visible content. The tool flags metadata changes separately so they do not get buried in the page diffs.
• Encrypted files. Password-protected PDFs cannot be read by the browser. Remove the protection before comparing.

Other Document Tools

Need to fix the pages before comparing? Merge, split, or rotate pages to isolate just the sections that matter. Compress a PDF after verifying no unwanted changes crept in. Or convert images or HTML to PDF if one of the versions you need to compare is not a PDF yet.

All comparison processing runs in your browser. No files are uploaded to any server.