Geometric Sizing

Also known as: geometric sizing, geometric bet sizing, geo sizing

Betting an equal pot fraction on every remaining street so the stack goes all-in by the river, maximizing value from a polarized range.

Geometric sizing pours the stack in over several streets using the same fraction of the pot each time, which gets you all-in exactly on the river and extracts the most from a polarised, nutted range. The per-street bet fraction over \(n\) remaining streets is

\[ f = \tfrac{1}{2}\left(\left(\tfrac{S}{P}+1\right)^{1/n}-1\right) \]

where \(S\) is the effective stack remaining and \(P\) the current pot. Because each bet grows the pot, a constant fraction compounds the pot geometrically — hence the name. Solvers favour it for value because it maximises total chips wagered while keeping the bluff-to-value-ratio consistent across streets, so the opponent stays indifferent on every node.

The sizing depends entirely on SPR: low SPR needs only a couple of medium bets, deeper SPR needs larger fractions or overbets to reach the river all-in. Geometric lines are a value/bet-sizing tool against ranges that can call multiple streets; against capped opponents a single large bet often prints more. Drill the math with the Geometric Sizing tool.