Introducing PDFMergely: private PDF tools that never upload your files
Today we are launching PDFMergely: a free set of PDF tools that run entirely in your browser. You can merge, split, compress, rotate, reorder, watermark, number, protect and unlock PDFs, and your files never leave your device while you do it.
No uploads. No servers. No sign-up. No watermarks added to your files.
The problem we set out to fix
Almost every online PDF tool works the same way: you choose a file, it uploads to a server, the server does the work, and you download the result. For a holiday itinerary that is fine. For a contract, a payslip, a passport scan, a medical form or a bank statement, it means handing your document to someone else's computer and trusting what happens next.
We did not want to ask for that trust, so we built the tools so the question never comes up.
How it works: move the code to the file
A normal web app keeps its code on a server, so your file has to travel to the code. We flipped that around. Modern browsers are powerful enough to read the files you choose and run real processing locally, so instead of sending your file to our code, we send our code to your browser. The PDF engine downloads once, then every operation runs on your device.
There is no upload step because there is nowhere to upload to. The part of a normal service that would receive your file simply does not exist here. A few browser technologies make it work:
- Your file stays in memory. The browser hands the app the file's bytes directly. They live in the tab, not on a server.
- Web Workers do the heavy lifting on a background thread, so the page stays responsive even on a large document.
- WebAssembly runs the parts that need to be fast, like encryption, at close to native speed.
When you download the result, the finished PDF is built right there on your device.
What you can do today
- Merge, split, reorder and rotate pages, or delete and extract them
- Compress PDFs to email them
- Add a watermark or page numbers
- Protect with a password, or unlock ones you own
Every tool is free and works on your phone in any modern browser, with no app to install. More tools are on the way.
Why this is different
- Privacy by architecture, not by promise. A privacy policy can change. The absence of an upload endpoint cannot be quietly walked back. We even lock the site down so file data has no network path to leave the page.
- It is fast. There is no upload to wait for, so processing starts the moment you drop a file.
- It works offline. After the first visit, the tools keep working with no internet connection at all. You can merge PDFs on a plane.
The honest tradeoffs
This is not magic. Because the work happens on your device, very large files depend on your device's memory, and a phone will not be as quick as a desktop. We think that is a fair trade for never having your documents leave your hands, and we design around it, for example by processing one page at a time.
Try it
Pick a tool and go. A good place to start is Merge PDF, Compress PDF or Protect PDF. If you want the longer version of how the privacy works, read how we built PDF tools that cannot see your files.
We would love your feedback. Tell us what to build next at feedback@pdfmergely.com.