Running a prize draw people will believe
You have entrants and a prize. How do you draw a winner in a way that the people who did not win will accept?
The hard part of a prize draw is not randomness. Any decent tool gives you that, and this site's methodology page explains where it comes from. The hard part is that nobody watching can see the randomness happen, so a draw is only as trustworthy as the process around it — and the most common mistakes are all process mistakes, not technical ones. This guide is about making a draw checkable by somebody who does not trust you, which is the only standard that matters.
Publish the entrant list before you draw, not after
This is the one that does the most work and the one most often skipped. If the list of entrants is fixed and visible before the draw happens, the only thing left to doubt is the draw itself. If the list appears afterwards, everything is in doubt — including whether the winner was on it.
For a small draw, a screenshot of the numbered list posted before you draw is enough. For anything larger or with a prize worth arguing about, post the list somewhere with a timestamp you do not control: a comment on the announcement post, a message in a group chat, an email to yourself. The point is not ceremony, it is that the list cannot be edited after the number comes out.
Number the list, and keep the numbers stable. A draw that produces a name is only as good as your ability to show that name was on the list; a draw that produces position 47 in a list everybody already has is checkable by anyone who can count. It also settles the two edge cases that otherwise cause trouble — duplicate entries, which stay as separate numbered lines if your rules allow multiple entries and are removed before numbering if they do not, and late entries, which simply do not appear because the list was fixed first.
Use a seed if you need to prove it afterwards
A seeded draw is reproducible: anybody with the seed, the entrant list and the tool can run it again and get the same winner. That turns "trust me" into "check it yourself", and it is the strongest guarantee available without a third party.
The catch is the order of operations, and getting it backwards makes the whole thing worthless. Publish the seed *before* the draw — a phrase nobody can predict, ideally one supplied by somebody else or taken from a public event like a lottery result or a closing price. Choosing the seed afterwards means choosing the winner, and a reader who knows what a seed is will assume that is what happened.
Note also what a seeded draw gives up, because it is a real trade rather than a free upgrade. Seeded output is deterministic and deliberately not cryptographically secure: anybody who knows the seed can reproduce the result, which is precisely the property that makes it checkable. That is exactly right for a raffle, where you want a sceptic to be able to rerun it, and exactly wrong for anything security-sensitive, where the same property would be the vulnerability. Never reuse a raffle seed as a password or a token.
Draw the reserves in the same run
Winners do not reply. If you draw one name, wait a week and then draw again, the second draw has a different entrant list — the first winner is out of it, and quite possibly some entrants have withdrawn. That is a second, unverifiable draw, and it is where a clean process usually falls apart.
Draw an ordered list instead: first, second, third and so on, in one run, published together. If the first does not respond by the deadline, the prize passes down a list everybody could already see. This is what larger raffles do and it costs nothing.
Publish the deadline with the order, and make it a date rather than a duration. "Seven days to claim" starts an argument about when the seven days began; "claim by the 14th" does not. If you are drawing several prizes rather than one, shuffle the whole entrant list once and read down it — first name takes the first prize, second the second — instead of running a fresh draw per prize, which multiplies the number of moments somebody has to trust.
Do not let an animation do the arguing
A spinning wheel is a good way to show a draw and a bad way to justify one. On this site — and on most others — the result is decided before the animation starts, and the spin is a rendering of a decision already made. That is not a criticism; an animation that genuinely resolved as it slowed would be harder to make fair, not easier.
It matters because the wheel invites a belief it cannot support. If somebody asks how you know the wheel was not weighted, the honest answer is that the wheel is a picture and the draw was the number behind it. Say that, and lean on the published list and the seed instead. A screen recording of a spin proves that a spin happened, not that it was fair.
Know when you are running something a regulator cares about
In the UK, a draw where entrants pay to enter and the prize is allocated wholly by chance is a lottery, and running one without a licence is an offence with narrow exemptions. The usual routes around it are a free entry method advertised as prominently as the paid one, or a genuine element of skill. Neither is a formality and both have caught out well-intentioned organisers.
This is a guide, not legal advice, and the rules differ by jurisdiction. If money changes hands for entry, check the position where you are before you promote the draw — that is a much cheaper conversation than the one afterwards.
The bottom line
Publish the entrant list first, publish the seed before the draw rather than after, draw the reserves in the same run, and never let a wheel animation stand in for the evidence. Those four things cost nothing and remove almost every objection anybody can raise.
Other guides
- Choosing a tournament formatKnockout, round-robin, Swiss, double elimination, ladder or boxes — what each costs in time and what each guarantees.
- Splitting a group fairlyTeams, pairs, rotations or a constraint solver — what 'fair' means in each case, and the ceilings a shuffle cannot get past.
- Proving a draw was fairWhat a seed actually gives you, why the order you publish it in decides everything, and where reproducibility is the wrong tool.