Free online tools upload your file to a server you know nothing about. OnDevice Tools can't - there is no backend. 64 utilities for developers and everyday work: JSON/XML/YAML/SQL formatters, regex tester, hashing, image compress/resize/convert, PDF merge and split, CSS generators, QR codes and financial calculators. Everything runs in your own tab. No sign-up, no upload, no limits. It works offline once loaded, and it's open source under AGPL so the claim is checkable rather than just stated.

Hi PH, I built this because I kept needing to format a config, compress a screenshot or decode a token, and every site I found wanted me to upload the file first. For a throwaway snippet that's fine. For a contract, an ID scan or a token from a live environment, it's a decision most people wouldn't make if the page said out loud what it was doing. So there's no server here. Your file is read, processed and handed back by your own browser. The fastest way to prove that to yourself: open DevTools, watch the Network tab, use any tool — nothing you typed appears in a request. Or turn off your wifi; it keeps working. It's free, ad-supported, and open source (AGPL). Would genuinely like to know which tool you'd want next.

ondevice-tools.org

64 free browser tools that never upload your data

64 free browser tools that never upload your data