How Plinko probabilities work
At every peg the ball goes left or right with equal chance. After n rows it lands in slot k if exactly k of its bounces went right, and the number of ways to do that is the binomial coefficient C(n, k). Divide by 2ⁿ, the total number of paths, and you have the slot's probability. The edges have exactly one path each, which is why they are so rare.
| Rows · risk | Edge slot pays | Either edge | Return |
|---|---|---|---|
| 8 rows · low | 5.6× | 1 in 128 | 98.98% |
| 8 rows · high | 29× | 1 in 128 | 99.06% |
| 12 rows · medium | 33× | 1 in 2,048 | 98.99% |
| 16 rows · low | 16× | 1 in 32,768 | 99.00% |
| 16 rows · medium | 110× | 1 in 32,768 | 98.99% |
| 16 rows · high | 1000× | 1 in 32,768 | 98.98% |
Rows and risk, in one sentence each
Rows set how far the ball can spread: more rows, more slots, and longer odds at the edges. Risk sets where the money sits: low risk pays something almost everywhere, high risk pays very little in the middle and a lot at the edges. The Plinko guide walks through each setting with examples.