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+251 Odds Explained

Decimal
3.51
American
+251
Fractional
251/100
Implied probability
28.49%
Polymarket
28¢
$100 wins
251.00
Inputs
Results
Decimal odds3.510
American
+251
Fractional
251/100
Implied probability
28.49%
Polymarket
28¢
Profit
251.00
Total return
351.00

3.510 decimal, +251 American, 28.49% implied probability

The price +251 converts to 3.51 decimal odds and 251/100 fractional odds. Read as a probability it says the bookmaker prices this outcome at 28.49%, 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 +251 pays

A 100 stake at +251 returns 351.00 in total: your 100 back plus 251.00 profit. To win exactly 100 you would stake 39.84. The table covers the stakes people actually use.

Payout by stake
StakeProfitTotal return
1025.1035.10
2562.7587.75
50125.50175.50
100251.00351.00
5001,255.001,755.00
1,0002,510.003,510.00

Break-even and long-run results

The implied probability of +251 is 28.49%, and that number is also the break-even win rate: win more often than 28.49% 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%-1.7%
50%75.5%
55%93.1%
60%110.6%
65%128.1%

At 28.49% implied, +251 is a moderate underdog. A bet here wins less than half the time by the bookmaker's reckoning, but each win pays 251.00 per 100. Draws in soccer, the second favourite in a three-horse race and road teams in close games are typical residents of this range.

The vig at +251

If both sides of a two-way market were priced at +251, the implied probabilities would add up to -43.02% above 100%. That excess is the overround, or vig; as a share of stakes it is a -75.50% 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.

+251 on a betting exchange

Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +251 is worth 3.460 decimal (+246 American); at 5% it drops to 3.384 (+238). Those are the bookmaker prices you would need to beat.

Effective odds on an exchange
CommissionEffective decimalEffective AmericanBreak-even
2%3.460+24628.90%
5%3.384+23829.55%

Same price in other formats

Nearby prices

Nearby prices

  • +241 · 3.41 · 29.3%
  • +246 · 3.46 · 28.9%
  • +249 · 3.49 · 28.7%
  • +250 · 3.50 · 28.6%
  • +252 · 3.52 · 28.4%
  • +253 · 3.53 · 28.3%
  • +256 · 3.56 · 28.1%
  • +261 · 3.61 · 27.7%

Frequently asked questions

What does +251 mean in betting?

+251 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +251 the implied probability is 28.49% and a 100 stake returns 351.00.

What is +251 in decimal odds?

+251 converts to 3.510 in decimal odds (usually shown as 3.51). Decimal odds are the total return per unit staked, so multiply your stake by 3.510 to get the return.

What is +251 as a fraction?

+251 is 251/100 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 +251?

A 100 stake at +251 wins 251.00 in profit and returns 351.00 including the stake. To win exactly 100 you would stake 39.84.

What win rate do I need at +251?

The break-even win rate equals the implied probability, 28.49%. Winning more often than that at this price is profitable over the long run; winning less often loses money.