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Compare Two PDFs Side by Side
Upload two PDF files and view any page from both documents side by side. Quickly spot differences between versions.
How to compare two PDFs online
- Load both files — drop your original PDF into the left slot and the revised version into the right slot, or use the file picker to choose each one.
- Pick a page to examine — select the page number from each document you want to view. The two pages render side by side at the same scale.
- Review the differences — scan the paired pages directly. Changed text, moved blocks, added images, or removed content become immediately apparent when the two versions sit next to each other at the same size.
What the side-by-side view actually shows you
Each PDF page is rendered to a canvas at full resolution, so the comparison is visual rather than text-only. That matters because PDFs do not always store content as plain text — they may embed text as vectors, use custom fonts, or place elements at absolute coordinates. A pixel-level render catches all of it. You can jump to any page in either file, which is useful when the two versions have different page counts or when a change appears several pages in. The independent page selectors let you align the exact sections you care about — compare page 4 of the draft against page 5 of the final, for example, if a page was inserted mid-document.
When to use a PDF comparison tool
The most common use case is contract revision review: a counterparty returns a redlined agreement as a new PDF, and you want to confirm exactly what changed before signing. Other situations include verifying that a re-exported or re-converted file looks identical to the source, checking that a printer-ready PDF matches the design proof, catching edits introduced during a translation or localization pass, and auditing whether a published regulatory filing matches the version that was internally approved. Any time you receive a PDF and need to answer the question "is this the same as what I sent?" this tool gives you a fast, reliable answer without installing software.
Frequently asked questions
- Does the tool compare text content or visual appearance?
Both. The tool renders each PDF page to a canvas and places the two pages side by side so you can scan them visually. Because rendering is pixel-based, it catches text changes, layout shifts, image swaps, and any other visual difference — not just body copy.
- What kinds of changes does it highlight?
Anything that affects the rendered appearance of a page: edited or deleted text, reformatted paragraphs, added or removed images, page margin changes, and footer or header updates. If it is visible on the page, the side-by-side view will expose it.
- Do both PDFs need to have the same number of pages?
No. You choose which page to view from each document independently. If the original has 10 pages and the revised version has 12, you can still compare any page from either file.
- Are my documents uploaded to a server?
No. Both files are processed entirely inside your browser using WebAssembly. Nothing is transmitted to any server, and no copy of your documents is stored anywhere outside your device.
- Can I download a diff report after comparing?
The tool is a visual comparison viewer, not a document diff exporter. To capture findings, use your browser's screenshot function or print-to-PDF on the comparison view. A dedicated export feature is on the roadmap.