What the spinner wheel does
A spinner wheel is a colorful circle split into as many slices as options you type. You hit Spin, the wheel speeds up, slows down and the arrow lands on a winner. It is the most visual and fun way to hand a decision over to chance, with no dice or slips of paper to fold.
Everything runs inside your browser: type one option per line (up to 100), the wheel is drawn instantly, and the winner is chosen with your system’s cryptographic random generator. No accounts, no ads glued to the button, and nothing ever leaves your device.
What people use it for
- Giveaways and raffles: type the entrants’ names and spin. Turn on “remove the winner” to draw prize after prize with no repeats.
- Deciding between options: which movie to watch, where to eat, who goes first in a game.
- In the classroom: cold-call a random student, set the order of presentations, or hand out tasks without arguments.
- Games and parties: replace the dice, or pick dares and forfeits.
- Who pays or treats: the wheel settles the lunch bill in seconds.
How to share your wheel with a link
This wheel is shareable. When you press Copy link, your options are stored inside the web address itself (encoded at the end of the URL). Anyone who opens that link sees the exact same wheel, with the same names, already loaded and ready to spin.
That is perfect for a group chat: build the wheel with your raffle entrants, copy the link, paste it in, and everyone can spin from their own phone. Nothing is saved on any server; all the information travels inside the link.
Fair randomness
A draw is only fair if every option has the same probability. This wheel does not use Math.random() (built for simulations, not draws). It uses crypto.getRandomValues, the browser’s cryptographically secure generator, with rejection sampling to remove the bias you would get from splitting 2³² numbers across a count that is not a power of two.
On top of that, the winner is decided before the animation, and the wheel simply brakes at the right spot: the speed, the number of turns and the stopping point have no effect on the outcome.
Worked example
On a wheel, each option takes an identical slice of the circle, so its probability is 1 / number of options:
| Options on the wheel | Angle of each slice | Probability of each |
|---|---|---|
| 2 | 180° | 50% |
| 4 | 90° | 25% |
| 5 | 72° | 20% |
| 8 | 45° | 12.5% |
| 10 | 36° | 10% |
With 8 names, each one owns 45° of the wheel and an exact probability of 1 ÷ 8 = 12.5%. Spin the wheel 8,000 times and each name comes up roughly 1,000 times, within the normal swing of chance.
Frequently asked questions
Is it really random?
Yes. The winner is drawn from crypto.getRandomValues, the same randomness source that powers security keys, and modulo bias is corrected with rejection sampling. No option is favored and the result cannot be predicted.
How do I run a fair draw?
Put each entrant on its own line (check there are no duplicate names or extra blank lines), spin once, and honor the first result. For several prizes, tick “remove the winner after spinning” and keep spinning so nobody can be picked twice.
Can I share my wheel with other people?
Yes. Press Copy link and share the address: your options travel inside the link, so whoever opens it sees your wheel already set up. It is the perfect way to run a transparent draw where everyone starts from the same wheel.
How many options does it take?
Up to 100. With many options the slices get thin and labels are shortened, but the wheel still works and every option keeps the same probability.