Moneyline (American) odds are centred on a 100 stake. A minus sign marks the favourite and tells you how much you must stake to win 100: at −150 you risk 150 to win 100. A plus sign marks the underdog and tells you how much a 100 stake wins: at +250 you win 250. A line of +100 is even money.
Implied probabilities follow directly. For −150 it is 150 ÷ (150 + 100) = 60%; for +250 it is 100 ÷ 350 = 28.57%. The calculator converts any moneyline into probability and into decimal and fractional odds, or works the other way from chances for and against, a probability or a fractional or decimal price. It also tells you whether the price makes the outcome a favourite or an underdog.
Enter a stake to see the total returned and the net profit if the bet wins, and a number of repetitions to see the probability of a winning or losing streak. In a two-way market the two implied probabilities add to more than 100% – the bookmaker’s vig – which the implied probability calculator can remove.
How to use the Moneyline Odds Calculator
- I know the odds as
- Chances for (winning outcomes)
- Chances against (losing outcomes)
- Probability of winning
- Fractional odds – first number (profit)
- Fractional odds – second number (stake)
- Decimal odds
- Moneyline odds (minus for favourites) — Type −150 for a favourite or 250 for +250.
- Stake (any currency)
- Times in a row
Everything is calculated in your browser, so results appear instantly and nothing you type is sent to a server.
How it works
Negative lines use |X|/(|X| + 100) and positive lines 100/(X + 100) for the implied probability. Decimal odds are its reciprocal; the moneyline is rebuilt from the decimal odds when another format is entered.
Worked example
A team is priced at −150. Implied probability = 150 ÷ 250 = 60%, so the chance of losing is 40%. Decimal odds = 1 + 100/150 = 1.6667 and fractional odds 2/3. A 100 stake returns 166.67, a 66.67 profit. Winning two such bets in a row has probability 0.6² = 36%.
Moneyline at a glance
| Moneyline | Implied probability | Profit on 100 |
|---|---|---|
| −300 | 75.00% | 33.33 |
| −200 | 66.67% | 50.00 |
| −150 | 60.00% | 66.67 |
| −110 | 52.38% | 90.91 |
| +100 | 50.00% | 100 |
| +150 | 40.00% | 150 |
| +250 | 28.57% | 250 |
Formula
Favourite (−X): probability = X ÷ (X + 100), profit = stake × 100 ÷ X
Underdog (+X): probability = 100 ÷ (X + 100), profit = stake × X ÷ 100
Worked example
Inputs — I know the odds as: American moneyline odds (e.g. −150 or +250); Moneyline odds (minus for favourites): -150; Stake (any currency): 100; Times in a row: 2.
Results — American moneyline odds = −150; Probability of winning (implied) = 60 %; Probability of losing = 40 %; Decimal odds = 1.6667; Fractional odds (profit/stake) = 2/3; Odds in favour (win : lose) = 3 : 2.
Key terms
- Decimal odds
- The total payout per 1 unit staked, stake included; 1 ÷ decimal odds is the implied probability.
- Fractional odds
- Profit ÷ stake, written like 5/2 – a winning 2 pays 5 profit.
- Moneyline odds
- American format: +250 is the profit on a 100 stake, −150 is the stake needed to win 100.
- Implied probability
- The chance of winning that a price represents, before any bookmaker margin is removed.
Frequently asked questions
How do moneyline odds work?
Negative numbers show the stake needed to win 100 (−150: stake 150 to win 100); positive numbers show the profit on a 100 stake (+250: win 250).
How do I convert a moneyline to probability?
Negative: |X| ÷ (|X| + 100), so −150 → 60%. Positive: 100 ÷ (X + 100), so +250 → 28.57%.
What does +100 mean?
Even money – stake 100 to win 100, a 50% implied chance, decimal 2.00.
How do I convert a moneyline to decimal odds?
Positive: 1 + X/100 (+250 → 3.50). Negative: 1 + 100/|X| (−150 → 1.667).
How much do I win on a −110 bet?
100/110 of the stake: a 110 stake wins 100 and returns 210.
How are parlay payouts calculated?
Convert each leg to decimal odds and multiply them, then multiply by the stake.