Edit PDFs without uploading them
In short: most free online PDF tools upload your documents to their servers. If you handle ID documents, payslips or contracts, choose a tool that processes files on your device: a browser tool that works locally, like LUNYCE, or software installed on your computer.
Why it matters
When a file is uploaded, it travels over the internet and is stored, even briefly, on someone else's server. Reputable services encrypt the transfer and delete files after a while, but you have to trust them. A tool that works locally removes that step: there is nothing to intercept, store or leak.
Three ways to edit PDFs without uploading them
| Option | Examples | Good for | Limits |
|---|---|---|---|
| Browser tools that work locally | LUNYCE | Nothing to install, works on computer and phone, free | Speed depends on your device for very large files |
| Desktop software | PDF24 Creator (Windows), Preview (Mac), LibreOffice | Working offline every day | Must be installed; not always available on phone |
| Self-hosted open-source tools | Stirling-PDF | Companies that want their own server | Needs technical setup |
How to check that a tool does not upload your files
- Read the tool's privacy page: it should say clearly whether files are uploaded and how long they are kept.
- Look at the progress bar: an “Uploading…” step means the file leaves your device.
- For a certain answer, open the browser's developer tools (Network tab), run the tool and check that no request carries your file.
What you can do on LUNYCE without uploading anything
- PDF: merge, split, compress, sign, edit, redact, protect, OCR, PDF to Word, PDF to Excel.
- Images: compress, resize, HEIC to JPG, remove EXIF data, blur a face or a number.
See also: LUNYCE vs iLovePDF · LUNYCE vs Smallpdf · Security.