A drawer of precise tools that keep your input to themselves.
ToolsDev exists for the moment you need an EMI, a formatted JSON file or a QR code, and want the answer in seconds — without a sign-up, an upload or an advert in the way.
What you type stays on your device
Every tool runs inside your browser. Nothing you type, paste or drop into a tool is uploaded — you can check the network tab yourself. Live pages (weather, rates, news) ask their sources only for what they show.
Tools work without a connection
Install the site or open a tool once, and the tool keeps working offline — its page says so when it does. Live pages need a connection. Useful on a train, in a basement office, or on a metered connection.
No sign-up needed
Open a tool and use it. Recent tools and favourites are remembered on this device. Signing in is optional and only keeps them in step across your devices; you can export or delete everything any time.
Honest about limits
Each tool says what it cannot do. If something genuinely needs a server, it is marked as such rather than faked.
Where to start
Type what you want to do on the home page, or browse every category. Read exactly how your data is handled on the privacy page, the rules for using the site in the terms, and how to reach us on the contact page.