About Slumpa
Slumpa is a free web app that brings together the random tools you would otherwise look up one at a time: dice, lots, names, numbers, colours, a card deck, a spinning wheel and a handful of party games. Everything runs in the browser, with no account and nothing to install.
Why Slumpa exists
Most random generators online do one thing each, are buried in ads, or ask you to sign up first. Slumpa was built as the opposite: one place where all the tools live, the page loads fast, and nothing stands between you and the draw.
The app is built as a PWA. You can add it to your home screen on a phone and keep using the tools without a connection once the page has loaded once.
How the randomness works
Every draw uses crypto.getRandomValues, the browser's cryptographic random number generator, rather than Math.random. On top of that it applies rejection sampling, which removes the systematic bias that creeps in when a random value is folded into a range with a modulo.
The result is that every outcome has exactly the same probability. For a dice that means all six faces are equally likely; for a raffle it means every entrant has the same chance.
22 languages, the same tools
Slumpa is available in 22 languages: the Nordic ones, the major Western European ones, the Central European ones and the Baltic ones. Each language has its own URLs, its own copy and its own content in the games – not machine-translated strings.
Switch language at the top of the page. The choice is stored locally and used the next time you open the home page.