To understand how to read betting odds, start with the price: it shows how much a winning bet could return for your stake. Decimal, fractional and American odds express that price in different ways, and none guarantees that an outcome will happen.
What betting odds tell you
Odds are the price offered for a selection. If the selection wins, the stake is settled at that price; the amount returned depends on both the odds and the stake.
We use three terms consistently: the stake is the amount wagered, profit is the amount won excluding the stake, and total return is profit plus the stake returned on a winning bet. A £10 stake that produces £10 profit therefore has a £20 total return.
Odds also imply a probability: the win rate suggested by the price before accounting for the bookmaker’s margin. That figure is not a guarantee, and it does not establish the outcome’s exact chance.
| Odds format |
What it communicates |
Simple equivalent |
| Decimal odds (2.00) |
Total return for each £1 staked, including the stake |
2.00 |
| Fractional odds (1/1) |
Profit relative to the stake |
1/1 |
| American odds (+100) |
Profit on a £100 equivalent stake |
+100 |
These three prices represent the same even-money odds. Our betting guides cover odds, markets and other betting topics, making them a useful next step for readers learning the terms.
Read decimal, fractional and American odds
Decimal odds
Multiply a stake by decimal odds to find the total return on a winning bet.
Fractional odds
Read the first number as the possible profit and the second as the amount staked to make it. At 6/4, a £4 winning stake makes £6 profit, and the original £4 stake is returned as well.
American odds
A plus sign shows the profit on a £100 equivalent stake: +200 means £200 profit for that reference stake. With -150, £150 is the amount needed to make £100 profit; the minus sign indicates the stake required for that reference profit.
The £100 reference is a comparison convention, not a minimum or required stake. You can wager a different amount and calculate the return in proportion to it.
Vegas odds usually means American odds. A plus or minus sign can also appear in a spread, but there it refers to points assigned to a team, not the odds price; the section on spreads below explains how to tell the difference.
At -110 American, the price converts to about 1.91 decimal (10/11 fractional). With a £10 winner, profit is about £9.09; including the returned stake, the payout is approximately £19.09 total return and £9.09 profit.
Calculate profit and total payout from a stake
For decimal odds, use total return = stake × decimal odds, then subtract the original stake to find profit. This formula assumes the bet wins; a losing selection does not receive a winning payout.
At +200 American, the equivalent price is 3.00 decimal (2/1 fractional). The £10 wager earns £20 profit (10 × 2); with the stake returned, that is £30 total return and £20 profit.
At -150 American, a £10 winner earns about £10 × 2/3 = £6.67 profit; adding the returned stake gives approximately £16.67 total return and £6.67 profit.
Displayed odds and currency amounts are rounded. A hand calculation using a displayed price can differ by a penny from a payout calculated using the full underlying odds.
Our free betting calculators give readers a practical way to check betting calculations alongside these examples.
Turn odds into implied probability
For decimal odds, divide 1 by the price to calculate raw implied probability. For example, 2.00 decimal implies 1 ÷ 2.00 = 50% before the bookmaker’s margin.
Convert American odds to decimal or fractional odds first, or use the direct formula. For a negative American price, divide the absolute odds by the absolute odds plus 100; for a positive price, divide 100 by the odds plus 100.
Implied probability is the arithmetic percentage indicated by a price. Break-even probability is the win rate needed over repeated bets at that price to break even, assuming ordinary win-or-lose settlement and no other costs. For a simple fixed-odds bet, the raw implied percentage and break-even threshold match, but neither tells you the outcome’s true likelihood.
A larger possible payout does not automatically make a bet better value. A longer price can simply reflect a lower implied probability, so compare the price with your assessment of the chance rather than looking at the return alone.
You need to win about 52.4 percent of your -110 bets just to break even.
Source: FOX Sports
Read moneyline, spread and over-under prices
A moneyline price is attached to an outcome, such as a team winning. The lower-return price often marks the favourite, while the higher-return price often marks the underdog, but the label does not guarantee the result.
A point spread has two separate parts: the points and the odds price. A team at -3.5 points must win by at least four points to cover; a team at +3.5 points covers by winning or losing by three points or fewer.
On an over-under, the number is the total goals or points line, and the price applies to betting over or under it. The line’s plus or minus is not an American odds sign.
A moneyline favourite can have plus points on a spread because the markets describe different outcomes: one prices a win, while the other prices a result against a points handicap. For football examples and market terminology, see our football betting guide.
Compare prices and account for bookmaker margin
Compare odds only when the outcome and settlement terms match. Convert the prices to one format and calculate the return for the same stake: a higher price means a higher return if that selection wins.
For cross-format comparisons, SportsLine lists the -100 conversion and SportsLine lists the +200 conversion.
| 1X2 outcome |
Decimal odds |
Fractional odds |
Raw implied probability |
| Home win |
2.00 |
1/1 |
50% |
| Draw |
3.50 |
5/2 |
About 28.57% |
| Away win |
4.00 |
3/1 |
25% |
The overround is the amount by which a market’s raw implied probabilities exceed 100%; a proportional calculation can also express the bookmaker margin.
To estimate margin-adjusted probabilities for a market, divide each outcome’s raw probability by the total of the raw probabilities. This proportional calculation is an estimate, not a guarantee of the true likelihood.
Prices can move when new information arrives or betting activity changes. A move changes the offered return and the probability implied by that price; by itself, it does not prove the outcome has become more likely.
Know how a bet is settled
A push, or tie in a market that allows one, generally returns the stake rather than settling the selection as a win or a loss. The precise result depends on the market’s settlement rules.
On a whole-number spread or total, the result can land exactly on the line and produce a push. A half-point line cannot land exactly on that number, so it removes that particular push outcome.
A returned stake is not profit. Do not use a winning-bet payout calculation for a selection that is void or pushed, because its settlement is different from a win.
Parlays, called accumulators in the UK, combine selections and display a combined price. Futures show a price on an outcome settled later, but the distinction between stake, profit and total return still applies to both.
A practical way to use the price
When working out how to read betting odds, identify the format, calculate the possible return, then consider the implied probability and settlement terms. Compare like with like, and treat the price as a payout calculation rather than a promise about the result.
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