Rigged · on purpose
This one is rigged, and I am not hiding it. It always lands on whoever you choose. And the bits it shows, and the modulo, genuinely check out.
Call the winning index t and the number of entries n.
Now v mod n is always t. That is one line.
No server, no clever technique. Print v in binary and
it is indistinguishable from a real bit string.
That is the entire point of this page.
When a drawing app shows you "here are the random bits we used" and "here is the modulo", it has guaranteed nothing. Pick the winner first, then produce a number that fits. Being able to recheck a calculation and being fair are two different things.
What actually works is the ordering. Fix the randomness first, and publish the evidence for it — a hash — before anyone knows the result. That removes the room to work backwards, by removing the time to do it in. The name for this is a commitment.
See the commitment on the real one →
Rigging is easy because ordinary random numbers are computed. Take a seed, multiply, add, take a remainder. Which means producing whatever output you want is just as easy.
There is a live demonstration on the real page: put in the same seed and the same "random" numbers come back, every time. It looks scattered, but anyone holding the seed knew all of it. That is a pseudo-random number.
Quantum is different here. A measurement outcome is not determined by any variable that existed before the measurement. There is no seed — not "we haven't found it", but Bell's theorem, a mathematical result confirmed experimentally (2022 Nobel Prize in Physics). So there is nothing to work backwards from.
Using it to quietly hand a win to someone in a real draw — please don't. It exists so that people know how easy this is. People who know stop trusting drawings that come with no evidence. That is the goal.
When showing it to someone, put it next to the real one. While the wheels are spinning you cannot tell them apart. The difference only appears when you check the commitment.