THE FORMULA
One entry’s share of the total
The wheel adds all active weights together. Each entry’s weight is then divided by that total to determine its expected probability.
INSIDE THE SPIN
Spin the Wheel Lab selects each result with cryptographically strong random values generated by your browser. The winner is chosen from the entries and weights currently on the wheel—then the animation carries the wheel to that result.
No mysterious wheel physics. No last-second switch. Just controlled chaos with documented rules.
Quick answer: the selection system chooses the result. The animation controls how that result is revealed.
THE SHORT ANSWER
What you see spinning is the reveal—not the mechanism deciding which entry wins.
Spin the Wheel Lab uses your browser to generate a cryptographically strong random value.
The wheel maps that value across the active entries according to their weights and selects one result. That result is then passed into the main wheel animation.
Winner selection uses the browser’s
crypto.getRandomValues()
method—not JavaScript’s standard
Math.random() function.
The animation cannot switch the selected entry. Speed, sounds, easing, and visual effects change the presentation—not the chosen result.
BEHIND THE BUTTON
The wheel follows the same selection sequence each time. It checks the available choices, calculates their probability ranges, selects one result, and then begins the main wheel animation.
The wheel uses the choices currently available for selection. If Eliminate removed a previous result, that entry is no longer part of the next spin unless it is restored.
Entries with equal weights receive equal shares of the total probability. Increasing an entry’s weight intentionally gives it a larger share.
Spin the Wheel Lab requests a cryptographically strong random value from the browser. That value is matched to one of the wheel’s cumulative probability ranges.
The chosen entry is passed into the main animation. The wheel then rotates to display the result that was already selected.
What the animation controls: timing, speed, easing, sounds, and presentation. What it does not control: which entry wins.
EQUAL-WEIGHT WHEELS
Yes. When every active entry has the same weight, each entry receives the same selection probability on every spin.
Each entry holds one of the four available weight units.
| ENTRY | WEIGHT | CHANCE |
|---|---|---|
| Choice A | 1 | 25% |
| Choice B | 1 | 25% |
| Choice C | 1 | 25% |
| Choice D | 1 | 25% |
Each spin is a new selection. Unless you remove or eliminate a result, an entry remains eligible even when it won the previous spin.
CONTROL THE PROBABILITY
A weight changes an entry’s chance relative to the total weight of every active entry. A higher weight makes a result more likely—it does not guarantee that result will win.
THE FORMULA
The wheel adds all active weights together. Each entry’s weight is then divided by that total to determine its expected probability.
The total weight is four.
| ENTRY | WEIGHT | EXPECTED CHANCE |
|---|---|---|
| Choice A | 1 | 25% |
| Choice B | 1 | 25% |
| Choice C | 2 | 50% |
THE REVEAL, NOT THE DECISION
No. The main wheel animation displays a result that has already been selected.
The wheel selects an entry from the active choices and their weights before the main rotation begins. The chosen entry is then passed into the animation so the wheel can finish on that result.
An animated wheel may appear to slow near one segment before continuing to another. That movement is part of the visual sequence—not evidence that an entry was favored, rejected, or switched at the last moment.
The simplest way to think about it: the selection system chooses the result; the animation makes the reveal worth watching.
RANDOM DOESN’T MEAN ALTERNATING
Because repeat results are a normal part of random selection. A previous winner is not automatically less likely merely because it appeared on the last spin.
Unless Eliminate is active, the wheel uses the same active entries and weights again. Past results do not change the next selection automatically.
This means a name, prize, or choice can win twice in a row—or several times during a short session—even when all entries have equal weights.
Before starting a no-repeat round, confirm how many distinct winners you need and make sure the wheel contains enough eligible entries.
TEST THE CURRENT SETUP
Spin Science runs 10,000 simulated selections using the wheel’s current entries, weights, and winner-selection method. It compares each entry’s expected probability with the percentage observed during the test.
Run against the wheel configuration currently loaded in your browser.
For every entry, Spin Science shows its weight, expected percentage, observed selection count, and observed percentage. This helps you inspect whether the setup behaves as expected across a large test batch.
The simulation uses the same weighted-selection function used by a regular wheel spin. It performs the selections without running 10,000 full visual animations.
Variation is expected. Observed percentages will normally differ somewhat from expected percentages. The test examines a large simulated batch; it does not promise what will happen during any individual spin.
KNOW YOUR SETUP
The probability changes when the active entries or their weights change. Visual styling and presentation settings do not alter the configured chances.
These actions change the pool or the probability assigned to it.
These settings can change how the wheel looks or feels.
Important: styling does not change the odds only when the entries and their weights remain unchanged. Always review the final list and weight settings before an important round.
CLEAR CLAIMS. NO LAB-COAT BLUFFING.
No independent certification or third-party audit is claimed. Spin the Wheel Lab documents its selection process and provides tools for inspecting the current wheel setup.
The wheel’s random source, weighted-selection method, winner timing, and testing behavior can be described from the implementation. Spin Science lets users compare expected probabilities with results from a large simulated test.
Those details provide useful evidence about how the wheel operates. They do not turn the site into an independent auditor, regulator, or certification service.
PRIZES, DRAWINGS & GIVEAWAYS
Yes—the wheel can randomly select from the entries you provide. It does not verify eligibility, establish promotion rules, or independently audit the drawing.
A trustworthy result starts with a reviewed list and rules that were established in advance. Complete these checks before the official selection begins.
Spin the Wheel Lab applies the current entry list and weights, generates a random value in the browser, and presents the selected result.
The organizer remains responsible for the promotion’s rules, participant eligibility, prize availability, required disclosures, records, platform requirements, and applicable laws.
PRIZES, DRAWINGS & GIVEAWAYS
Yes—the wheel can randomly select from the entries you provide. It does not verify eligibility, establish promotion rules, or independently audit the drawing.
A trustworthy result starts with a reviewed list and rules that were established in advance. Complete these checks before the official selection begins.
Spin the Wheel Lab applies the current entry list and weights, generates a random value in the browser, and presents the selected result.
The organizer remains responsible for the promotion’s rules, participant eligibility, prize availability, required disclosures, records, platform requirements, and applicable laws.
BENEATH THE FLOORBOARDS
A compact reference for visitors who want the implementation details without digging through the full wheel code.
CODE REVIEWED
crypto.getRandomValues().
1.
1 during winner selection.
crypto.getRandomValues(). If secure random selection is
unavailable, the wheel should ask the visitor to update or change
browsers instead of silently using a weaker winner-selection method.
Last reviewed against the wheel code: October 19, 2026
Web Crypto technical referenceTHE FINAL LAB NOTE
A wheel is useful when a set of acceptable choices needs one impartial pick. You prepare the options and rules. Spin the Wheel Lab selects among the active entries using the probabilities you configure.
Have a question about a result or wheel setting? Send a Lab Note or review the Legal Lab .
You found Vortex. Now send the challenge to someone else and see if they can spot him too.