7 outs on the flop: chance to hit

27.84% is the exact chance by the river when you count 7 outs on the flop. Read on for the odds against, the shortcut figure and a full table of bet sizes with a call or fold verdict.

Chance to hit by the river

27.84%

7 outs, two cards to come

  • Chance on the next card14.89%
  • Odds against by the river2.59 : 1
  • Rule of 4 estimate+0.16 points from the exact chance28%

The count behind 7 outs on the flop

Between one chance in five and two in five, 27.84% is a draw worth playing when the bet is not oversized.

  • Unseen cards47
  • Your outs7
  • Cards that miss40
  • Pairs of cards with no out780
  • Pairs with at least one out301
  • Chance by the river27.84%
  • Chance on the next card14.89%
  • Odds against hitting2.59 : 1
  • Estimate from the rule of 428%
  • Error of the rule of 4+0.16 points

Chance by the river = 1 - C(u - k, 2) / C(u, 2), with u = 47 unseen cardsFor 7 outs: 1 - C(40, 2) / C(47, 2) = 1 - 780 / 1,081 = 27.84%Next card = 7 / 47 = 14.89%

Of the 1,081 pairs that two cards can make from the 47 unseen, 780 contain only misses. The other 301 hold at least one out, which is 27.84% of the pairs.

The quick estimate of 28% and the exact 27.84% nearly agree, separated by 0.16 points.

The adjusted rule only applies from the flop above 8 outs, so 7 outs on the flop use the plain rule of 4: 4 x 7 = 28%.

Which holding has 7 outs?

This count has no one textbook draw behind it. It is the total you get after adding up several draws and checking for overlap.

An out that also completes a better hand for a rival is a poor out. With one shared out among your 7 outs, the chance by the river falls from 27.84% to 24.14%, a loss of 3.70 points.

7 outs on the flop when some outs are shared with a better hand
Shared outsEffective outsChance by the riverChance given up
0727.84%0.00 points
1624.14%3.70 points
2520.35%7.49 points
3416.47%11.38 points

The bets 7 outs can call on the flop

Draw the line at 27.84%: any bet that needs less equity than that is a call. Here that covers 4 of the 12 bet sizes.

Work the price backward from 27.84% and you find a limit of 62.84% of the pot: $62.84 into a $100 pot.

7 outs on the flop against every bet size, with your chance by the river at 27.84%
Bet sizeEquity a call needsMargin over itVerdict
1/4 pot16.67%+11.18 pointsCall
1/3 pot20.00%+7.84 pointsCall
2/5 pot22.22%+5.62 pointsCall
1/2 pot25.00%+2.84 pointsCall
2/3 pot28.57%-0.73 pointsFold
3/4 pot30.00%-2.16 pointsFold
full pot33.33%-5.49 pointsFold
1.25x pot35.71%-7.87 pointsFold
1.5x pot37.50%-9.66 pointsFold
2x pot40.00%-12.16 pointsFold
3x pot42.86%-15.01 pointsFold
4x pot44.44%-16.60 pointsFold

Nearby counts on both streets

Counts near 7 sit side by side below, on the flop and on the other street. One out is worth around 3.61 points on this page.

Counts near 7: the chance by the river on the flop and on the turn
OutsFlop, by the riverTurn, by the river
520.35%10.87%
624.14%13.04%
7 (this page)27.84%15.22%
831.45%17.39%
934.97%19.57%

When a bet buys only one card

Think about what the bet buys. If you must call again on the turn, only 14.89% counts for the flop call. A half-pot price of 25.00% leaves -10.11 points, which is a fold.

Drop to the next-card chance and the number of calls goes from 4 to 0 out of 12.

How this is computed

The chance to hit by the river from the flop is 1 - C(u - k, 2) / C(u, 2), where u = 47 unseen cards and k is your effective outs. For 7 outs that is 1 - 780 / 1,081 = 27.84%. The chance on the next card is k / 47, here 14.89%.

The rule of 4 figure is 4 x k, here 28%, and its error is that figure minus the exact chance in percentage points, here +0.16 points.

Assumptions: every unseen card is equally likely, and no card is removed for an opponent's hand, so this is the chance to hit your outs, not your equity against a named hand. A call is paid in full, so the pot after it holds the pot plus two bets. Here the pot is $100.

Computed from the closed form by the GeorgeLiPoker math library.

Updated

Questions

How often do 7 outs hit on the flop?

With 7 outs on the flop you hit by the river 27.84% of the time, about 28 of every 100 hands, and on the next card 14.89%. The odds against hitting by the river are 2.59 : 1, since 780 of 1,081 pairs of unseen cards hold no out.

How does the quick rule compare with the exact chance for 7 outs?

The rule of 4 gives 28% for 7 outs against an exact 27.84%, an error of +0.16 points. That is close enough to use at the table.

How big a bet can I call with 7 outs on the flop?

At 27.84% by the river, you can call 4 of the 12 bet sizes. A half-pot bet needs 25.00%, a margin of +2.84 points, so against half the pot the verdict is Call. The largest bet you can call is 62.84% of the pot, or $62.84 on a $100 pot.

How many points do I lose if outs are shared with a better hand?

Take them off the count first. With one shared out the chance by the river falls from 27.84% to 24.14%, and with 3 shared it falls to 16.47%, a loss of 11.38 points. The effective count is then 4 outs.

Check your own hands against the numbers

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