gizmobench

Wheel of Names

Paste a class register, a raffle list or the people in the room, spin, and let the wheel settle on one name. The name is chosen by your browser's cryptographic random generator before the wheel starts turning, with every name given exactly the same chance, so the spin is a fair show of a result that already exists. Set aside takes each winner off the wheel for the spins that follow, which turns one spin into a running order where nobody is called twice, and Reset puts the whole list back for next time. The list stays in your browser, with no upload and no account.

Wheel of names

Entries appear on the wheel

Nothing on the wheel yet.

Decided before the wheel movesSet aside really removes an entryNothing leaves your browserNo account, up to 500 entries
Winner
Spin length
Sound

Ready. Press Spin, or the space bar.

Press Space to spin without reaching for the mouse. Entries are separated by line breaks and by commas, so a column pasted from a spreadsheet and a comma list both work. Editing the list rebuilds the wheel and clears the history. Reset puts every entry back without touching the list, and Shuffle changes the order on the wheel without changing anyone's chance.

The spin decides nothing. The winner is drawn from crypto.getRandomValues the moment you press Spin, and the angle the wheel stops at is worked out from that winner's segment before the first frame is drawn. Watching it slow down cannot change who came out. Each entry on the wheel has the same chance: the index is taken by rejection sampling rather than a remainder, so no position in your list is favoured, and the spin length changes how many turns you watch, not the odds. An entry typed twice is two segments, which is how you give someone two chances, and the header over the list counts the repeats so it is never a surprise.
Accuracy. The winner is drawn from the browser's cryptographic random generator before the wheel begins to turn, with every entry given the same chance, and the spin only shows a result that has already been decided. A name typed twice is two entries and has two chances.

Common questions

How do I use it to call on students?
Paste the register once, one name per line or separated by commas, and it is remembered in this browser. Leave Winner on Set aside and press the space bar or Spin to call the next student: each name leaves the wheel when it wins, the header over the list counts how many have been set aside, and nobody is called twice until everyone has had a turn. Reset puts the whole class back on the wheel for the next lesson without retyping anything. Adding a late arrival to the list rebuilds the wheel, so do it between rounds.
Is it fair enough for a raffle or a giveaway?
Yes. The winner is drawn from crypto.getRandomValues, the browser's cryptographic generator, mapped onto the list by rejection sampling so that every name has exactly the same chance, and the draw is over before the wheel begins to move. Nothing about the animation, the spin length or the order on the wheel can change the result, and there is no server involved that could be asked to. A name entered twice is two segments with two chances, which is how you give someone extra tickets, and the list header reports the repeat so it cannot happen by accident. Copy history as text puts every spin on the clipboard if you need to post the result.
How do I pick who goes first?
Put the players on the wheel and spin once: the name under the pointer goes first. To draw a full playing order, leave Winner on Set aside and keep spinning; the history under the controls lists Spin 1, Spin 2 and so on, which is the order. If instead you want a fresh draw each round where the same person can be picked again, switch Winner to Keep in wheel.
How many names fit on the wheel?
Up to 500. Names are printed on the segments while there is room and drop off as the list grows, but the winner is always written under the wheel and in the history, so even a wheel too crowded for labels still tells you who won. For a list longer than 500 the tool points you to the random name picker, which draws from any length of list without drawing a wheel.
Can the students tell it was not rigged?
The page says how it works in plain terms: the draw comes first, from the browser's own cryptographic generator, and the wheel's stopping angle is calculated from the name that was drawn. Shuffle changes the order the names sit in on the wheel without changing anyone's chance, and spinning again with Keep in wheel really can pick the same name twice, which is what a fair draw does. The only way to weight the wheel is to type a name twice, and the header over the list shows when that has happened.

The winner is drawn from the browser's cryptographic random generator before the wheel begins to turn, with every entry given the same chance, and the spin only shows a result that has already been decided. A name typed twice is two entries and has two chances.