How Plinko odds work
A ball dropped onto a board with n rows makes n left-or-right decisions, each a fair coin. The bucket it ends in is simply the number of rights it took, so the probability of bucket k is C(n,k)/2n — the binomial distribution. On 16 rows the middle bucket collects 12,870 of the 65,536 possible paths (19.6%) and each corner collects one (0.0015%).
The paytable is built so that the sum of (probability × multiplier) comes to about 0.99 at every setting. That is why the calculator's RTP hovers at 99% whether you pick 8 rows low or 16 rows high — the operator's edge is roughly 1% of every drop regardless of how spiky the board looks.
Reading the results
- Drops paying ≥1× is the share of balls that return at least your stake. It ranges from about 80% (16 rows, low) to 21% (16 rows, high).
- Std dev per drop is the size of a typical swing relative to your bet: 0.33× on low, 6.6× on high. Multiply by the square root of the number of drops to size a session.
- Odds of top counts both corners. The 1,000× on 16 rows high is 1 in 32,768.
Every casino in our ranking uses this format. Rainbet's BOOST20 code adds 20% rakeback, which you can price with the rakeback calculator.