How It Works

1. The random numbers

We use crypto.getRandomValues, the cryptographic random number generator built into every modern browser. It draws on the operating system's entropy sources and is designed so that its output cannot be predicted. It is far stronger than the everyday Math.random that many simple sites use.

2. No bias toward any entry

Turning a large random number into "one of 7 entries" naively (taking the remainder) slightly favours some entries. We avoid that by discarding the rare draws that would cause the imbalance and drawing again, so each entry's chance is exactly one in the number of entries.

3. The winner is chosen before the wheel moves

When you press spin, the winner is picked first. The animation is then calculated to stop on that entry, with a small random offset within its slice so it looks natural. The spin's speed, length and starting point are decoration: they do not change who wins.

4. Shuffles for multiple picks

For several names, teams or giveaway winners we shuffle the whole list with the Fisher–Yates method, using the same random numbers, and read off the result. Every order is equally likely.

5. Your lists stay with you

Your entries are kept in your own browser's storage so they are there next time. They are not sent to our server. "Copy link" puts the entries inside the part of the link after the # sign, which browsers do not send to the server either.

Want more chances for one entry?

List it more than once. Two lines of "Pizza" among ten lines gives pizza a two-in-ten chance.