Roulette Generator
Completely free, browser-based roulette that does not require an app.
Items and probabilities (weights) can be freely customized.
Weight: higher = more likely to win (default: 1)
💡 Tap an item to delete/edit
- No spins yet
About
This is a completely free tool that allows anyone to easily create original roulette on a browser and does not require installation.
It is very useful in situations such as ``deciding the lunch menu,'' ``punishment games at drinking parties,'' and ``present lottery.'' You can also create a roulette wheel with a biased probability of winning just by setting the name and "weight (probability)".
In addition to saving the created roulette in your browser, you can also share it with friends and SNS using a dedicated URL. Complete offline processing and random generation (crypto) ensure safe and fair drawings.
How to Use
Basic usage
- In the "Items" tab, add the candidates (names, etc.) that you want to include in the roulette.
- Press the "SPIN" button to spin the roulette and display the lottery results.
- You can also easily add lunch and punishment game suggestions from "Presets".
Useful functions
- 🎯 Weight (probability): Increasing the number (1 to 99) will expand the roulette area and make it easier to win.
- 🎭 Production: You can set "feint production (re-acceleration after stopping)" and "elimination mode (erasing items that have been hit once)".
- 🎬 Theater mode: This is useful when displaying only the roulette on the screen and displaying it on a projector at an event.
Use Cases
Live streaming planning and lottery
Turn on "Elimination Mode" and take turns choosing winners in distributed giveaways, or deciding which game to play next. It also looks great in theater mode.
Drinking party punishment game roulette
Use weighting to create thrilling games with a low probability of a big loss, such as "One-shot gag (weight 10)" and "Treat everyone (weight 1)."
Glossary
- Roulette
- A random selection method using a spinning wheel and pointer to choose one item. Probabilities can be equal or weighted.
- Weight
- A numeric value controlling the probability of each item being selected. Higher weight means higher probability. Setting "Prize:1, Blank:9" gives a 10% win rate.
- Easing
- An animation acceleration/deceleration pattern. Roulettes use ease-out curves (fast start → gradual slowdown → stop) to simulate realistic spinning.
- Canvas API
- A web standard API for drawing graphics on HTML Canvas elements. Used for rendering the spinning roulette animation.
- Fisher-Yates Shuffle
- An algorithm for randomly reordering an array with equal probability for all permutations. Ensures unbiased random selection in the roulette.
- requestAnimationFrame
- A Web API that synchronizes animations with the browser's refresh rate (typically 60fps). Enables smooth roulette spinning.
FAQ
- Q.Is the selection truly random?
- Yes. JavaScript's pseudo-random number generator (Math.random()) is used, providing statistically unbiased results. However, cryptographic-grade randomness is not guaranteed.
- Q.Can I set different probabilities for each item?
- Yes. Assign "weight" values to each item. For example, "1st Prize:1, 2nd Prize:3, Consolation:6" gives 10%, 30%, 60% probabilities respectively.
- Q.What's the maximum number of items?
- There's no hard limit, but 20-30 items is recommended for readability. Too many items make individual segments too small to read.
- Q.Does it work on mobile screens?
- Yes. Touch controls are fully supported, and the roulette works smoothly on smartphones and tablets.
- Q.Is the result history saved?
- Results are stored in the browser until the page is reloaded. You can also export results as CSV format.
- Q.Can I customize the roulette colors?
- Each item is automatically assigned a unique color. Color palette customization is also available.