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+645 Odds Explained

Decimal
7.45
American
+645
Fractional
129/20
Implied probability
13.42%
Polymarket
13¢
$100 wins
645.00
Inputs
Results
Decimal odds7.450
American
+645
Fractional
129/20
Implied probability
13.42%
Polymarket
13¢
Profit
645.00
Total return
745.00

7.450 decimal, +645 American, 13.42% implied probability

American odds of +645 mean

a 100 stake wins 645

. In decimal notation that is 7.45, in fractional notation 129/20, and the implied probability is 13.42%. On a prediction market the same price is a 13¢ share.

What +645 pays

A 100 stake at +645 returns 745.00 in total: your 100 back plus 645.00 profit. To win exactly 100 you would stake 15.50. The table covers the stakes people actually use.

Payout by stake
StakeProfitTotal return
1064.5074.50
25161.25186.25
50322.50372.50
100645.00745.00
5003,225.003,725.00
1,0006,450.007,450.00

Break-even and long-run results

The implied probability of +645 is 13.42%, and that number is also the break-even win rate: win more often than 13.42% 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
13%-3.1%
50%272.5%
55%309.8%
60%347.0%
65%384.3%

+645 is a longshot. The bookmaker prices the outcome at 13.42%, and the payout of 645.00 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 +645

If both sides of a two-way market were priced at +645, the implied probabilities would add up to -73.15% above 100%. That excess is the overround, or vig; as a share of stakes it is a -272.50% 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.

+645 on a betting exchange

Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +645 is worth 7.321 decimal (+632 American); at 5% it drops to 7.128 (+613). Those are the bookmaker prices you would need to beat.

Effective odds on an exchange
CommissionEffective decimalEffective AmericanBreak-even
2%7.321+63213.66%
5%7.128+61314.03%

Same price in other formats

Nearby prices

Nearby prices

  • +595 · 6.95 · 14.4%
  • +620 · 7.20 · 13.9%
  • +635 · 7.35 · 13.6%
  • +640 · 7.40 · 13.5%
  • +650 · 7.50 · 13.3%
  • +655 · 7.55 · 13.2%
  • +670 · 7.70 · 13.0%
  • +695 · 7.95 · 12.6%

Frequently asked questions

What does +645 mean in betting?

+645 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +645 the implied probability is 13.42% and a 100 stake returns 745.00.

What is +645 in decimal odds?

+645 converts to 7.450 in decimal odds (usually shown as 7.45). Decimal odds are the total return per unit staked, so multiply your stake by 7.450 to get the return.

What is +645 as a fraction?

+645 is 129/20 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 +645?

A 100 stake at +645 wins 645.00 in profit and returns 745.00 including the stake. To win exactly 100 you would stake 15.50.

What win rate do I need at +645?

The break-even win rate equals the implied probability, 13.42%. Winning more often than that at this price is profitable over the long run; winning less often loses money.