Chop, merge, and transform your files — right in your browser.

What is ChopFile?

ChopFile is a free, privacy-first PDF toolkit. Unlike most online PDF tools that upload your files to cloud servers, ChopFile uses modern browser technologies — including Web Workers and WebAssembly — to process everything locally on your device. When you merge, split, rotate, or convert a PDF, the work happens entirely inside your browser tab. Your documents never leave your computer.

Why use a browser-based PDF tool?

Most people don't think twice about uploading a PDF to a cloud service — until they realize what's in it. Bank statements, tax returns, medical records, legal contracts, and HR documents all pass through server infrastructure you have no visibility into. With ChopFile, the answer to "where does my file go?" is simple: nowhere. It stays on your device throughout the entire process.

Beyond privacy, browser-based tools are faster for small to medium tasks. There's no queue, no server-side processing wait, and no download delay from a remote data center. Your file is ready as soon as your device is done processing it.

How ChopFile tools work

Each tool is powered by open-source libraries running inside your browser:

• pdf-lib handles merging, splitting, rotating, page organization, metadata editing, and adding page numbers. It reads and writes PDFs natively in JavaScript.
• PDF.js (Mozilla's open-source PDF engine) renders PDF pages for the image conversion tool, drawing each page onto an HTML canvas element at high resolution.
• Web Workers run heavy processing in a background thread so the page stays responsive while large files are processed.

All tools are free to use with no file count limits, no account required, and no usage caps. The only constraint is your device's available memory.