How many riffle shuffles randomise a deck of cards? Shuffle a real Gilbert-Shannon-Reeds deck, watch its rising sequences, play the Bayer-Diaconis card-guessing game, and read the exact total variation distance computed in your browser from Theorem 1 of Bayer & Diaconis (1992). The famous answer is seven; the honest answer is a range from four to thirteen, depending on the question. An independent reimplementation of published mathematics by Dave Bayer and Persi Diaconis (Ann. Appl. Probab. 2(2), 1992) and L. N. and L. M. Trefethen (Proc. R. Soc. A 456, 2000), on the shuffle model of Gilbert (1955) and Reeds (1981). Runs entirely client-side: no model, no credits, no account.

Every public app is built from a security-scanned skill and must pass a clean scan — skill and frontend — before it can be listed. Have a skill of your own? Turn it into an app — or read the step-by-step walkthrough.