Oracle

How it works

The numbers come from the LfD QRNG, a quantum random number generator at Leibniz Universität Hannover that offers its numbers to everyone. Our server fetches them 1 KB at a time and keeps them in memory. Every byte is used once and then thrown away.

A byte becomes a card without bias. If the byte falls outside the largest range that divides evenly by the number of cards left, it is discarded and the next one is taken. A simple remainder would make some cards come up more often.

If the LfD does not answer within a second and a half, the server shuffles with the ordinary Cloudflare generator, and the page says so under the draw. A draw is called quantum only when its numbers really were quantum.

Quantum numbers: LfD QRNG, Leibniz Universität Hannover