Do you have the odds to call with an open-ended straight draw?

An open-ended straight draw has 8 outs: 17.0% on the turn, 17.4% on the river, and 31.5% by the river when both cards are guaranteed.

8 Outs

17.0% Hit on the next card (flop)

17.4% Hit on the river (turn)

31.5% By the river, both cards guaranteed

Table shortcut, outs × 2 for each card you see: 8 × 2 = 16% for a one-card call, and 8 × 4 = 32% when this flop call guarantees both cards. Both land within 1.4 points of the exact 17.0% and 31.5%, close enough to use at the table.

One-card direct odds assume you fold after a miss and pay no further bets. Use by-the-river odds when this call guarantees both cards, such as an all-in or a guaranteed free river.

Eight cards make your straight. On one-card direct odds: 17.0% from the flop and 17.4% from the turn, which on direct odds alone calls a bet of about a quarter of the pot on either street. The 31.5% two-card figure prices a flop call that guarantees both cards, and then a bare open-ender can call up to about 85% of the pot. When only the next card is guaranteed, anything bigger than a quarter-pot bet needs implied odds.

On one-card direct odds, 8 outs can call a bet up to about 26% of the pot on the flop and up to about 27% of the pot on the turn on direct odds alone. When a flop call guarantees both cards, including all-in or a free river, both cards count, and then 8 outs can call a bet up to about 85% of the pot. Anything bigger has to be paid back by what you win when you hit.

Quick tip: An open-ender hits the next card 17.0% of the time, enough for about a quarter-pot bet on direct odds.