How online PDF tools handle your files, server upload versus in-browser processing, and a simple checklist to keep sensitive documents private.
Most of us have uploaded a PDF to some random website at least once to merge it, compress it or pull the text out. It is convenient, but it also means handing a copy of your document to a stranger's server. Whether that is a problem depends on what the document contains and how the tool works. This article explains the difference and gives you a simple checklist.
You pick a file, the website sends it over the internet to its own computers, processes it there and sends the result back. This is how many popular converters work. Your file exists on someone else's machine, at least for a while. A responsible company deletes it quickly and protects it properly, but you have to take its word for that.
Modern browsers are powerful enough to read PDFs, run OCR and draw images on their own. In this model the website sends you the code once, and the work happens on your phone or computer. The file is opened by the page running on your device and is not transmitted for conversion. This is how Docsworker works.
For these, prefer a tool that processes locally, or a service you already have a trust relationship with.
It is honest to say that local processing is not a magic shield. You are still loading code from a website, so you should trust the site you use. Your own device matters too: a browser that is out of date, or a computer shared with other people, carries risks no tool can remove. Keep your browser updated and use a screen lock.
All twelve Docsworker tools run in your browser. Text extraction, OCR, image conversion, signatures and watermarks happen on your device, with no account and no sign-up. The tools use well-known open-source libraries that are loaded when the page opens. You can read the details in our Privacy Policy and see what each tool does on the tools page.
If you want to see it in action, try the PDF to Text tool with a document you are comfortable testing with, then run the offline test above.
It depends on the website. A service that uploads your file hands a copy to its servers, so you are trusting its security and retention practices. For sensitive files, a tool that works inside your browser avoids that step completely.
Load the page, then switch to airplane mode or disconnect from the internet and try the tool with a small file. If it still works, the processing is happening on your device. Tools that rely on a language download for OCR may need a connection the first time.
Passport and ID scans, bank statements, medical records, contracts and anything with passwords or account numbers should only go to services you trust, or be processed locally.
Related tools: Add Signature · Image to PDF