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+850 Odds Explained

Decimal
9.50
American
+850
Fractional
17/2
Implied probability
10.53%
Polymarket
11¢
$100 wins
850.00
Inputs
Results
Decimal odds9.500
American
+850
Fractional
17/2
Implied probability
10.53%
Polymarket
11¢
Profit
850.00
Total return
950.00

9.500 decimal, +850 American, 10.53% implied probability

The price +850 converts to 9.50 decimal odds and 17/2 fractional odds. Read as a probability it says the bookmaker prices this outcome at 10.53%, 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 11¢.

What +850 pays

A 100 stake at +850 returns 950.00 in total: your 100 back plus 850.00 profit. To win exactly 100 you would stake 11.76. The table covers the stakes people actually use.

Payout by stake
StakeProfitTotal return
1085.0095.00
25212.50237.50
50425.00475.00
100850.00950.00
5004,250.004,750.00
1,0008,500.009,500.00

Break-even and long-run results

The implied probability of +850 is 10.53%, and that number is also the break-even win rate: win more often than 10.53% 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
11%4.5%
50%375.0%
55%422.5%
60%470.0%
65%517.5%

+850 is a longshot. The bookmaker prices the outcome at 10.53%, and the payout of 850.00 per 100 staked is the compensation for how rarely it lands. Longshots carry more margin than any other part of the market, which is why devigging methods disagree most at prices like this one.

The vig at +850

If both sides of a two-way market were priced at +850, the implied probabilities would add up to -78.95% above 100%. That excess is the overround, or vig; as a share of stakes it is a -375.00% 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.

+850 on a betting exchange

Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +850 is worth 9.330 decimal (+833 American); at 5% it drops to 9.075 (+807). Those are the bookmaker prices you would need to beat.

Effective odds on an exchange
CommissionEffective decimalEffective AmericanBreak-even
2%9.330+83310.72%
5%9.075+80711.02%

Same price in other formats

Same price in other formats

Nearby prices

Nearby prices

  • +800 · 9.00 · 11.1%
  • +825 · 9.25 · 10.8%
  • +840 · 9.40 · 10.6%
  • +845 · 9.45 · 10.6%
  • +855 · 9.55 · 10.5%
  • +860 · 9.60 · 10.4%
  • +875 · 9.75 · 10.3%
  • +900 · 10.00 · 10.0%

Frequently asked questions

What does +850 mean in betting?

+850 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +850 the implied probability is 10.53% and a 100 stake returns 950.00.

What is +850 in decimal odds?

+850 converts to 9.500 in decimal odds (usually shown as 9.50). Decimal odds are the total return per unit staked, so multiply your stake by 9.500 to get the return.

What is +850 as a fraction?

+850 is 17/2 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 +850?

A 100 stake at +850 wins 850.00 in profit and returns 950.00 including the stake. To win exactly 100 you would stake 11.76.

What win rate do I need at +850?

The break-even win rate equals the implied probability, 10.53%. Winning more often than that at this price is profitable over the long run; winning less often loses money.