ODDS BASICS
Moneyline odds explained: from a price to a probability
A moneyline is a price on an outright winner. Negative odds show the amount risked to make 100 units of profit; positive odds show the profit on a 100-unit stake. Neither number is a guaranteed prediction.
You can understand a sports-picks board more clearly by separating three numbers: the listed price, the probability implied by that price, and any independent estimate of the team's chance. This guide walks through the first two. Every example below is hypothetical, not a current selection.
What do −150 and +150 mean?
At −150, a successful 150-unit stake earns 100 units of profit, with the original stake also returned. At +150, a successful 100-unit stake earns 150 units of profit. A losing stake loses the amount risked. These conventions are illustrated in Caesars: Sports Wagering Basics (PDF); settlement details depend on the specific market and operator's rules.
| Price | Example stake | Profit if successful | Implied probability |
|---|---|---|---|
| −200 | 200 units | 100 units | 66.67% |
| −150 | 150 units | 100 units | 60.00% |
| +100 | 100 units | 100 units | 50.00% |
| +150 | 100 units | 150 units | 40.00% |
| +200 | 100 units | 200 units | 33.33% |
Profit versus total return: use the same stake
The 100-unit convention describes a ratio, not a required stake. To compare prices, hold the hypothetical stake constant. For a stake S, positive odds +A produce profit S × A/100 on a win; negative odds −A produce profit S × 100/A. Total return is that profit plus the original stake.
| Moneyline | Net profit on a win | Total returned on a win |
|---|---|---|
| −200 | 10 units | 30 units |
| −150 | 13.33 units | 33.33 units |
| +100 | 20 units | 40 units |
| +150 | 30 units | 50 units |
| +200 | 40 units | 60 units |
For example, a 50-unit total return at +150 includes the 20-unit stake; the gain is 30 units, not 50. If that selection loses under ordinary win/loss settlement, the net result is −20 units and nothing is returned. These examples ignore fees, taxes and promotional terms, and round displayed amounts to two decimals where needed.
A refunded stake is different from a winning profit. If the applicable rules make the selection a push, returning the 20-unit stake produces zero net profit. A tied game is not automatically a push: the selected market and time period decide settlement. See our two-way and three-way market examples before treating a draw as a refund.
How to calculate implied probability
For a negative price, take its absolute value and divide by that value plus 100. For a positive price, divide 100 by the price plus 100. Multiply by 100 to display a percentage.
Positive: 100 ÷ (odds + 100)
Why does that formula work? Ignoring pushes and fees, break-even probability is stake divided by stake plus potential profit. At −150, that is 150 ÷ 250 = 60%. At +150, it is 100 ÷ 250 = 40%. These are price-derived thresholds, not measured team abilities.
Why both sides can add up to more than 100%
Suppose Team A is −150 and Team B is +130 in a two-outcome market. Team A implies 60%; Team B implies 100 ÷ 230, or about 43.48%. Together they imply 103.48%. That excess is called the overround. It reflects margin in the quoted prices, rather than an extra possible outcome.
A simple proportional normalization divides each side by the total: A becomes 60 ÷ 103.48, about 57.98%, and B becomes about 42.02%. Use unrounded inputs for the calculation. This produces a pair that sums to 100%; it does not prove those are the true probabilities or reveal exactly how the bookmaker allocated its margin.
Overround is not the same as realized profit
The excess above 100% describes the quoted prices. It is not automatically the percentage of stakes a bookmaker keeps or a bettor loses. Some references call the entire sum the overround; here we explicitly distinguish the total from its excess.
Consider an original hypothetical two-outcome market priced at −120 on both sides, with no draws, refunds, fees or promotions. Each side implies 120 ÷ 220 = 54.545…%. The total is 109.09%, an excess of 9.09 percentage points.
Now suppose the operator takes 120 units on each side: 240 in total. Whichever side wins, the winning customer receives 220 units including their stake. The operator retains 20 ÷ 240 = 8.33% of the stakes, not 9.09%. The denominators differ.
| Stakes on A / B | Operator net if A wins | Operator net if B wins |
|---|---|---|
| 120 / 120 units | +20 units | +20 units |
| 180 / 60 units | −90 units | +130 units |
In the second row, total stakes remain 240, but the winning payout is either 330 or 110. Actual receipts, payouts and outcomes determine the realized result; quoted odds alone do not.
Economist Karl Whelan's explanation of bookmaker margins derives a margin from the total implied probability under an equal-margin assumption across outcomes, and explains that assumption's limits. Proportional normalization is therefore a calculation with assumptions, not independent evidence of a team's true probability. Keep a prediction's price, estimated chance and observed results separate.
Margin reference checked September 26, 2026. The −120 examples are original hypothetical cash-flow calculations, not operator or site performance.
Check that the prices describe the same market
- Use both sides from the same bookmaker and collection time.
- Check whether the market includes overtime or uses regulation time only.
- Do not apply a two-outcome calculation to a three-way market with a draw. See the two-way versus three-way comparison for a worked example.
- Keep a timestamp: a saved price and a current price may differ.
How this relates to our daily five
Monitor Sports Picks starts with normalized moneyline probabilities. When both teams have enough recorded games, our provisional method adds a season-record adjustment. The displayed estimate can therefore differ from the normalized market. Read the full calculation and limitations before interpreting it as evidence of an advantage.
The next distinction is just as important: a likely winner can still have an unfavorable price. A probability ranking is not a profitability ranking.
Source note: Caesars' guide supports the moneyline and payout conventions. The hypothetical probability table and normalization example are our own calculations. Source checked September 23, 2026.
Prices are observations at a particular time. Learn how to distinguish publication time from price collection time in our guide to odds timestamps and changing prices.