Random Wheel Spinner

The winner is chosen before the wheel starts turning, and the wheel is then rotated to land on that slice. Doing it this way means the result never depends on how long the animation ran, what frame rate the device managed, or when you released the pointer, all of which are ways a spinner can quietly become unfair.

1. Paste or type your names into the options box, one per line. Blank lines and stray spaces are ignored, so a list copied out of a register or a spreadsheet column works as it is.
2. Check the slice count shown under the wheel. It tells you how many names the wheel actually read, which is the quickest way to catch a name that shared a line with another.
3. Turn on "remove the winner after each spin" if you want every name used once. Leave it off if each spin should be independent.
4. Press spin. The wheel turns for about four seconds and the winner is shown as text under the wheel as well as on the rim.

• The draw uses the browser cryptographic generator with rejection sampling, so every slice is equally likely and no slice is favoured by a rounding shortcut.
• Slices are drawn with a conic gradient, so any number of names from 2 to 60 divides the circle exactly rather than leaving a seam.
• Names are printed on the rim for wheels of 24 or fewer. Above that the wheel stays colour-coded and the winner is read from the result panel instead.
• Removing the winner after each spin turns the wheel into a draw without replacement, which is what you want for an order of play rather than a single decision.
• The winner is announced in a live region as text, so the outcome does not depend on seeing the wheel at all.

A repeated name is the simplest way to make one entry likelier than the others. Entering a name twice on a wheel of 10 gives it two slices out of 11, so its chance goes from 10 percent to roughly 18 percent. This is worth knowing in the other direction too: a class list with two pupils called Sam gives the name Sam twice the chance of coming up, which is usually not what the person spinning intended.

Six spins of a six-name wheel will not give you each name once. That is not a fault in the wheel. Independent draws repeat and skip, and roughly one pair of consecutive spins in six lands on the same name. The remove-the-winner option exists precisely for the times you wanted each name used once.

Two limits are worth knowing before you rely on the wheel for something that matters. A list longer than 60 lines is silently cut to the first 60, so a pasted register of 90 pupils leaves 30 of them off the wheel with no warning; the slice count under the wheel is the number to check. Removing the winner matches on the text of the name, so two identical lines are both removed together rather than one at a time.

The wheel is the right tool when people are watching. For a decision nobody is watching, the random number picker is faster, and for odds that are not equal the weighted random picker states each chance as a percentage before you draw rather than asking you to pad the list with repeats.