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+256 Odds Explained

Decimal
3.56
American
+256
Fractional
64/25
Implied probability
28.09%
Polymarket
28¢
$100 wins
256.00
Inputs
Results
Decimal odds3.560
American
+256
Fractional
64/25
Implied probability
28.09%
Polymarket
28¢
Profit
256.00
Total return
356.00

3.560 decimal, +256 American, 28.09% implied probability

The price +256 converts to 3.56 decimal odds and 64/25 fractional odds. Read as a probability it says the bookmaker prices this outcome at 28.09%, which is the share of the time you would need to win just to break even. A prediction market would quote the same chance as 28¢.

What +256 pays

A 100 stake at +256 returns 356.00 in total: your 100 back plus 256.00 profit. To win exactly 100 you would stake 39.06. The table covers the stakes people actually use.

Payout by stake
StakeProfitTotal return
1025.6035.60
2564.0089.00
50128.00178.00
100256.00356.00
5001,280.001,780.00
1,0002,560.003,560.00

Break-even and long-run results

The implied probability of +256 is 28.09%, and that number is also the break-even win rate: win more often than 28.09% of the time at this price and you profit in the long run, win less often and you lose. The table shows the return on stake at a few win rates, including the break-even rate itself.

Return on stake by long-run win rate
Win rateReturn on stake
28%-0.3%
50%78.0%
55%95.8%
60%113.6%
65%131.4%

+256 is an underdog price: the bookmaker gives this outcome an implied chance of 28.09%, and the payout of 256.00 on 100 reflects it. Underdogs in this band are where public money and bookmaker margin often disagree, so it pays to compare prices across books before taking one.

The vig at +256

If both sides of a two-way market were priced at +256, the implied probabilities would add up to -43.82% above 100%. That excess is the overround, or vig; as a share of stakes it is a -78.00% margin for the bookmaker. Removing it leaves fair odds of 2.00 decimal ( +100) on each side. Use the devig calculator to do the same for any market.

+256 on a betting exchange

Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +256 is worth 3.509 decimal (+251 American); at 5% it drops to 3.432 (+243). Those are the bookmaker prices you would need to beat.

Effective odds on an exchange
CommissionEffective decimalEffective AmericanBreak-even
2%3.509+25128.50%
5%3.432+24329.14%

Same price in other formats

Same price in other formats

Nearby prices

Nearby prices

  • +246 · 3.46 · 28.9%
  • +251 · 3.51 · 28.5%
  • +254 · 3.54 · 28.2%
  • +255 · 3.55 · 28.2%
  • +257 · 3.57 · 28.0%
  • +258 · 3.58 · 27.9%
  • +261 · 3.61 · 27.7%
  • +266 · 3.66 · 27.3%

Frequently asked questions

What does +256 mean in betting?

+256 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +256 the implied probability is 28.09% and a 100 stake returns 356.00.

What is +256 in decimal odds?

+256 converts to 3.560 in decimal odds (usually shown as 3.56). Decimal odds are the total return per unit staked, so multiply your stake by 3.560 to get the return.

What is +256 as a fraction?

+256 is 64/25 in fractional odds, the traditional bookmaker notation where the top number is profit and the bottom number is stake.

How much do I win on a 100 bet at +256?

A 100 stake at +256 wins 256.00 in profit and returns 356.00 including the stake. To win exactly 100 you would stake 39.06.

What win rate do I need at +256?

The break-even win rate equals the implied probability, 28.09%. Winning more often than that at this price is profitable over the long run; winning less often loses money.