The short version
- The tool builds a list of active options and their effective weights.
- Your browser supplies a cryptographically strong random value.
- The tool maps that value to one active option.
- The wheel calculates a final rotation that places the selected segment under the pointer.
- The animation moves to that position and displays the selected result.
Separating selection from animation matters. A slow device, animation frame, sound setting, or wheel duration does not change which option was selected.
Where the random value comes from
The tools use the browser Web Crypto interface rather than Math.random(). Web Crypto provides random values generated by the browser for security-sensitive uses. Tiny Fate Toolbox converts those values into a number in the interval used by the current wheel.
No remote server chooses the answer. The list and the selection remain on the device running the wheel.
Equal-chance wheels
On the Yes or No Wheel, YES and NO each occupy half of the probability range, so each has a 50% chance on every spin. On the Name Picker and Custom Wheel, every active list entry receives one equal share.
If a name appears twice, those are two separate entries and therefore two separate chances. Disabled entries and blank labels are excluded. Removing a winner changes the active list for the next spin, but it does not change the result of a completed spin.
Weighted wheels
A weight is a relative amount, not a required percentage. The probability for one option is:
option probability = option weight ÷ total active weight
For weights 6, 3, and 1, the total is 10. The three probabilities are therefore 60%, 30%, and 10%. Weights 60, 30, and 10 create exactly the same proportions. An active option with a weight of zero cannot be selected.
How the selected segment reaches the pointer
After selection, the wheel knows the start and end angle of the winning segment. It chooses a landing position inside that segment and adds full rotations for the visible spin. The final angle places the chosen segment beneath the fixed pointer. The visual slice sizes and the selection calculation use the same effective weights.
Why fair results can look uneven
Fair does not mean alternating or perfectly balanced in a short sequence. A fair Yes or No Wheel can produce several YES results in a row. A 10% weighted option can appear twice in a small set of spins. Probability describes the process and long-run tendency, not a schedule for the next few outcomes.
See Why Random Results Look Uneven in Small Samples for worked examples.
What we test
- Probability totals and zero-weight behavior.
- Cumulative selection boundaries for weighted options.
- Landing geometry across wheels with two to one hundred options.
- Selection bounds for browser-generated random values.
- Local history limits, deletion, migration, and storage failure behavior.
What this method does not guarantee
A browser wheel is useful for low-stakes choices and demonstrations, but it is not a certified random-number generator, audited drawing service, or tamper-evident record. Do not use it for gambling, financial allocation, regulated lotteries, legal selection processes, or any decision that requires independent verification.