+121 Odds Explained
- Decimal
- 2.21
- American
- +121
- Fractional
- 121/100
- Implied probability
- 45.25%
- Polymarket
- 45¢
- $100 wins
- 121.00
- American
- +121
- Fractional
- 121/100
- Implied probability
- 45.25%
- Polymarket
- 45¢
- Profit
- 121.00
- Total return
- 221.00
2.210 decimal, +121 American, 45.25% implied probability
+121 is an American price:
the plus sign marks an underdog, and the number is the profit on a 100 stake
. Every other format describes the same chance: 2.21 decimal, 121/100 fractional, 45.25% implied probability, 45¢ on Polymarket.
What +121 pays
A 100 stake at +121 returns 221.00 in total: your 100 back plus 121.00 profit. To win exactly 100 you would stake 82.64. The table covers the stakes people actually use.
| Stake | Profit | Total return |
|---|---|---|
| 10 | 12.10 | 22.10 |
| 25 | 30.25 | 55.25 |
| 50 | 60.50 | 110.50 |
| 100 | 121.00 | 221.00 |
| 500 | 605.00 | 1,105.00 |
| 1,000 | 1,210.00 | 2,210.00 |
Break-even and long-run results
The implied probability of +121 is 45.25%, and that number is also the break-even win rate: win more often than 45.25% 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.
| Win rate | Return on stake |
|---|---|
| 45% | -0.6% |
| 50% | 10.5% |
| 55% | 21.6% |
| 60% | 32.6% |
| 65% | 43.7% |
An implied probability of 45.25% makes +121 a near-even price. This is the natural home of handicap and over/under markets, where the bookmaker adjusts the line rather than the price and both sides are quoted a shade under 2.00 decimal.
The vig at +121
If both sides of a two-way market were priced at +121, the implied probabilities would add up to -9.50% above 100%. That excess is the overround, or vig; as a share of stakes it is a -10.50% 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.
+121 on a betting exchange
Exchanges charge commission on net winnings, so the price you see is not the price you get. At 2% commission +121 is worth 2.186 decimal (+119 American); at 5% it drops to 2.149 (+115). Those are the bookmaker prices you would need to beat.
| Commission | Effective decimal | Effective American | Break-even |
|---|---|---|---|
| 2% | 2.186 | +119 | 45.75% |
| 5% | 2.149 | +115 | 46.52% |
Same price in other formats
Nearby prices
Nearby prices
Frequently asked questions
What does +121 mean in betting?
+121 is an American price. Positive numbers show the profit on a 100 stake; negative numbers show the stake needed to win 100. At +121 the implied probability is 45.25% and a 100 stake returns 221.00.
What is +121 in decimal odds?
+121 converts to 2.210 in decimal odds (usually shown as 2.21). Decimal odds are the total return per unit staked, so multiply your stake by 2.210 to get the return.
What is +121 as a fraction?
+121 is 121/100 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 +121?
A 100 stake at +121 wins 121.00 in profit and returns 221.00 including the stake. To win exactly 100 you would stake 82.64.
What win rate do I need at +121?
The break-even win rate equals the implied probability, 45.25%. Winning more often than that at this price is profitable over the long run; winning less often loses money.