The tools
The name wheel picks one entry from a list you paste, the team generator splits names into balanced groups, the number generator draws integers from a range, and the other tools cover coin flips, dice, yes/no, list order and random letters.
How randomness works
The browser's Web Crypto API supplies raw 32-bit values (crypto.getRandomValues). For a bounded integer, values outside a multiple of the range are rejected and drawn again, so every integer in the range is equally likely. There is no Math.random fallback anywhere in this site.
How the wheel picks a winner
The winner is drawn first with that uniform integer. The wheel rotation is then computed so the center of that segment stops exactly under the pointer; the spin animation only moves toward that fixed target. Editing is locked while the wheel spins, so the announced winner is always the segment at rest.
Teams and numbers
- Teams are built by shuffling the list with Fisher-Yates and dealing names round-robin: every name appears once, and sizes differ by at most one.
- When repeats are off, numbers are drawn with a sparse Fisher-Yates sample — time and memory depend on how many numbers you ask for, not on how wide the range is.
- Duplicates in your own list are kept by default; each copy counts as its own entry until you explicitly deduplicate.
- Teams can be built by a number of teams or by a maximum group size: round-robin dealing keeps the sizes within one, and no group is larger than the size you set.
- Session histories (coin flips, dice rolls, yes/no answers) stay in the page memory and disappear when you close or reload the tab.
What stays on your device
Every entry, team and number is processed in the page. Nothing is uploaded, and tool inputs are never sent to analytics. The name wheel and the team generator store named lists in this browser only after you press a save button; JSON files and share links are also created locally. Keep different classes or meetings as separate lists and delete any list you no longer need.
Accessibility
Results and errors are announced to screen readers, the wheel can be spun from the keyboard, controls keep visible focus, and animations collapse when your system asks for reduced motion.