ICM

The Independent Chip Model (ICM) is a mathematical method for converting tournament chip stacks into their real-money equity, given the prize structure and the number of players left. Its central insight is that tournament chips are not linear cash: doubling your stack does not double your money, because survival and pay jumps carry value of their own. Worked example: four players remain, paying $50, $30, $20 and nothing, and all four have equal stacks. By symmetry each player's ICM equity is about $25 — the $100 prize pool shared four ways — not the $100 a winner-takes-all reading would suggest. Growing from 20 big blinds to 40 does not double your equity, because the looming pay jumps matter more than raw chips. This is why ICM tightens your calling ranges near the bubble: you fold hands you would happily call with on a pure-chip basis, since busting forfeits all your prize equity, a loss costlier than the chips alone imply. ICM matters most around the bubble — the last finishing position before the money — and at the final table, where it shapes push/fold decisions and who can apply pressure to whom. The common mistake is playing pure chip-EV, as in a cash game, on the bubble, and busting just short of a payout by calling off a marginal edge. See also the Chip Leader, Heads-Up play, the bubble, GTO and Equity.