Krazy 7 — A spec-sheet reference for classic "sevens" | krazy-7.com
Three-of-a-kind odds are multiplication: count the stops on each reel and multiply.
Every classic three-reel machine has a fixed number of stopping positions per reel. The total number of outcomes is the product of those counts, and a jackpot that needs one specific stop on each reel occurs exactly once in that product of spins, on a single payline.
Take the classic 22-stop reel. Three reels give 22 x 22 x 22 = 10,648 combinations, so a single-hit jackpot — one jackpot stop per reel — pays at 10,648:1. A machine with 20 stops per reel gives 20 x 20 x 20 = 8,000 combinations, or 8,000:1 jackpot odds.
On narrow screens, swipe or scroll the plate sideways.
Virtual stops extend the arithmetic without enlarging the reels. The machine's internal map holds more positions than the physical strip shows, and several map positions can point to the same physical stop. With 64 virtual stops per reel, the combination count is 64 x 64 x 64 = 262,144, so a single-hit jackpot pays at 262,144:1.
The calculation runs in four steps: find the stop count per reel, multiply the three counts together, check how many stops carry the jackpot symbol on each reel, and divide the total combinations by the product of jackpot stops. One jackpot stop per reel is the simplest case and the one quoted in paytable math.
This arithmetic also explains paytable design. A machine with 10,648 combinations can afford a modest top award on a single line; a machine with 262,144 combinations can advertise a far larger one, because the jackpot combination arrives proportionally less often. The machines built on these structures are ranked on the index home page.
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