It is a fair question, and one worth asking before you use a wheel to hand out a prize or settle an argument. If you are running a giveaway, the whole point is that nobody can accuse you of steering the result. So how much can you actually trust the spin?
Where the result comes from
The wheel you see spinning is an animation. The outcome is decided by a random number produced by your own browser, and the animation simply rotates to land on whichever segment that number selected. The visual is for you; the decision happens in a fraction of a second before the wheel starts moving.
Strictly speaking, this is pseudo-random. The number comes from an algorithm rather than from a physical process like a dice throw. In practice the distinction does not matter for choosing a name or a restaurant: the results are evenly spread, nobody can predict them, and no segment is favoured over another.
What actually makes a spin fair
The randomness is rarely the weak point. These things are:
- Duplicate entries. If a name appears twice on the wheel, it has double the chance of winning. Check your list before you spin, especially if you pasted it from a spreadsheet or a comments thread.
- Segment size. Every entry gets an equal slice, so an equal chance. If you want weighted odds, add an entry more than once on purpose, and say so.
- Re-spinning. Spinning again because you did not like the first result is the single most common way a fair draw stops being fair. Decide in advance that the first spin counts.
- Removing winners. Drawing several winners? Take each one off the wheel before the next spin, or the same person can win twice.
Proving it to other people
Fairness you cannot demonstrate is not much use in a public giveaway. A few habits make the result easy to defend:
- Show the full entry list on screen before spinning, so everyone can see who is on the wheel.
- Record the spin in one continuous take rather than posting a screenshot of the result.
- Announce the rules first, including how many winners there are and what happens to duplicates.
- Do it live if you can. Nothing settles the question faster than an audience watching in real time.
For more on structuring a draw people will trust, see our guide on how to run a fair giveaway.
One thing a wheel cannot do
Randomness is only appropriate when every option is genuinely acceptable to you. A wheel is excellent for choosing between four restaurants you would all happily eat at. It is a poor way to make a decision where one outcome would be a mistake. If you find yourself hoping for a particular result while the wheel is still turning, you already know your answer, and you did not need a spin to find it.
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