Frequently Asked Questions

Absolutely. This is the most important feature of MusePDF. The 61 local tools run 100% in your browser, so your file is processed on your device and is not uploaded. A few optional cloud features (AI, very large files) send the file, or the text they need, to our servers for that step only; they are labelled, they run only when you pick them, and nothing is uploaded until you do.

The 61 local tools are completely free, with no hidden fees, no subscription and no usage limits. Optional cloud features consume server time, so they are metered by usage — some will be paid once they launch.

After you load the website for the first time, most tools will work completely offline! Because all the processing libraries are loaded into your browser, you can disconnect from the internet and continue to merge, split, compress, and edit your PDFs securely. Some niche tools that require external data (like Markdown to PDF with web images) may need a connection.

For the local tools there is no artificial cap on file size or usage — the only practical limit is your own computer's memory, so very large files take longer. If a file is too large for your browser to handle, the tool tells you before it starts.

Failures are rare but can happen for a few reasons:

• The PDF might be corrupted or not compliant with standard specifications.
• The file could be encrypted with a password you don't have. Please use our Decrypt tool first.
• The file might be a special "XFA" or dynamic form-based PDF, which some of our tools cannot process.

We care about your privacy. MusePDF uses Google Analytics (through Google Tag Manager) to count anonymous visits and see which tools are used — no personal information. Analytics loads only after the page has finished loading and runs in cookieless mode (no cookie, no identifier), and it does not receive a file name, file content or search text.

MusePDF is built on the power of modern web technologies. We primarily use JavaScript libraries like PDF-lib.js and PDFKit.js that are compiled to run efficiently in your browser via WebAssembly. This allows for powerful, server-like processing inside your browser, so for these tools your data stays on your machine.

It is used only to produce your result for that one step, and cloud steps are always opt-in. A cloud feature uploads the file, or the part of its text it needs, for that step only — and it never runs unless you choose it.