Spin the Wheel

How to use the wheel

1. Add your entries in the box, one per line — names, teams, chores, prizes or yes/no. Up to 200 lines; blank lines are ignored. The wheel redraws as you type, and the line under the box shows each entry’s chance.
2. Spin with the button, by tapping the wheel, or by pressing the space bar. The winner appears in a window when the wheel stops.
3. Remove winner & spin again takes that entry off the list and spins straight away, so nobody is picked twice. Put back removed restores everyone.
4. Full screen (or F) fills a projector or TV with just the wheel; Esc leaves it. Shuffle and Sort A–Z reorder the slices, and the sample lists get you started quickly.

If your device is set to reduce motion, the wheel turns less than one full revolution in under a second instead of spinning for several seconds, and the confetti is switched off. The result is exactly as random either way.

How the wheel picks fairly

Many online wheels simulate a physical spin and read off wherever it happens to stop. This one does it the other way round: the winner is chosen first, and the animation is then aimed at that slice. The choice uses crypto.getRandomValues, the cryptographically secure random generator built into every modern browser, which supplies a whole number from 0 to 4,294,967,295. Turning that into one of n entries needs care: if you simply took the remainder after dividing by n, some entries would have one extra number behind them. So the wheel throws away the few numbers at the very top of the range and draws again:

n = number of entries limit = 4,294,967,296 − (4,294,967,296 mod n) draw r until r < limit winner = entry number (r mod n), counting the first line as 0

Every entry then has exactly the same number of possible values of r behind it, so each has a chance of exactly 1 in n. The spot where the pointer stops inside the winning slice is picked separately and is only for show. The “How the pick is made” box under the wheel shows the actual random number and the division for every spin.

Worked example

The sample wheel has 8 names: Ava, Mateo, Priya, Jamal, Sofia, Liam, Mei and Noah. Because 4,294,967,296 is exactly 8 × 536,870,912, no number needs rejecting. Suppose the generator returns 123,456,789: 123,456,789 ÷ 8 = 15,432,098 remainder 5. Counting from 0, entry 5 is the sixth line, so Liam wins, and the wheel is spun so the pointer comes to rest on Liam’s slice. With 7 names instead, 4,294,967,296 mod 7 = 4, so the limit is 4,294,967,292 and the four values from 4,294,967,292 to 4,294,967,295 would be redrawn — an event with a chance of about 1 in a billion per spin, but leaving it in would make three of the names very slightly more likely than the others.

Removing each winner turns the wheel into a fair draw without replacement: with 25 students, the first pick is 1 in 25, the next 1 in 24, and so on, and every possible order of the class is equally likely — the same as drawing names from a hat.

Using it in the classroom

• Calling on students fairly. Used as a random name picker, a visible spin feels fairer than a teacher’s choice and keeps everyone ready to answer. Remove each winner so the whole class gets a turn before anyone is called twice.
• Order of presentations, groups and jobs. Spin for who goes first, or put tasks on the wheel and let each group spin. For a complete random order, press Shuffle and read the list from the top.
• Projectors and smartboards. Full screen scales the wheel to the display, with large labels and a large pointer name; the space bar spins it from a wireless keyboard or clicker that sends Space.
• Privacy. Student names stay in your browser. Nothing is uploaded or stored on our servers.

Giveaways, streams and decisions

For a giveaway, list each eligible entrant once (or once per entry if people earned extra entries — the chance line shows the effect), and show the spin on screen or record it so viewers can see the draw. Because nothing is seeded, a spin cannot be reproduced later, so capture the winner window. Formal sweepstakes and contests can have legal requirements about how winners are drawn; follow your official rules, and treat this page as a convenient tool, not legal advice. For quick two-way decisions, a coin flip is simpler; for games, try the dice roller.

Saving and sharing your wheel

The list is saved automatically in this browser’s local storage under the name reeliy-wheel, together with your spin-time setting and any removed names, so it is still there when you come back on the same device. To use the same wheel somewhere else, press Copy link to this wheel. The entries travel in the link after the # sign — the fragment, which browsers keep to themselves rather than sending to the website — and whoever opens the link sees the same entries in the box. Anyone with the link can read the names, so share it only with people who should see them.