Compare PDF
Compare two PDF files online for free. See a line-by-line breakdown of what text changed between two versions of a PDF, generated in your browser. Processed locally in your browser — the file is never uploaded.
How to use compare pdf
- Choose a file
Select the two PDFs you want to compare.
- Set the options
Fill in any fields the tool needs, such as a page range or watermark text.
- Run and download
The result is generated locally and downloaded straight to your device.
Features
Pages are processed with pdf-lib/pdf.js entirely in your browser.
Very large PDFs are rejected with a clear message instead of freezing the tab.
The file is discarded from memory once you leave the page.
Supported formats and limitations
PDF files and browser-supported source formats vary by tool.
Use cases include personal workflows, content preparation, and quick checks. Review output before relying on it for legal, financial, accessibility, or production decisions.
Frequently asked questions
Is my PDF uploaded?
No. Processing happens locally using the pdf-lib/pdf.js libraries loaded into your browser.
Is there a size limit?
Files over 100 MB are rejected because very large PDFs can exhaust browser memory.
Does this change my original file?
No. A new file is generated and downloaded; your original file on disk is untouched.