Every bet you place has a potential payout determined by the odds. Whether your sportsbook displays Decimal, American, or Fractional odds, the math always comes down to two numbers: your profit (what you gain) and your total payout (profit plus your original stake returned).
This guide covers the exact formula for each odds format, with worked examples you can verify against our Odds Converter & Payout Calculator.
Payout vs Profit: The Key Distinction
Before diving into formulas, it is important to understand the difference between these two terms, because different odds formats calculate different things:
Profit = the money you gain above your original bet. Total Payout = profit + your original stake returned to you.
If you bet $50 and win $75 in profit, your total payout is $125. Decimal odds calculate total payout directly. American and Fractional odds calculate profit, to which you add your stake. They all reach the same number — the format just determines which formula you use.
Decimal Odds: The Simplest Formula
Decimal odds (used in Europe, Australia, and most of the world) are the easiest to calculate because there is one formula that works for every bet — favorite or underdog.
Total Payout = Stake × Decimal Odds
Profit = Payout − Stake
Decimal odds always include the stake. An odds of 2.00 means you get back double your money (your stake plus equal profit). An odds of 1.50 means you get back 1.5× your stake. Anything below 2.00 is a favorite; above 2.00 is an underdog.
| Stake | Decimal Odds | Payout (Stake × Odds) | Profit |
|---|---|---|---|
| $50 | 1.50 | $75.00 | $25.00 |
| $50 | 2.50 | $125.00 | $75.00 |
| $20 | 3.75 | $75.00 | $55.00 |
| $110 | 1.91 | $210.10 | $100.10 |
The last row (1.91) is the Decimal equivalent of −110 American — the standard vig line. A $110 bet at 1.91 returns $210.10, producing roughly $100 profit. Quick mental shortcut: for Decimal odds, subtract 1 and multiply by your stake to get profit. 2.50 → 1.50 × $50 = $75 profit.
American Odds: Two Formulas (Positive and Negative)
American odds require two different formulas depending on the sign. This is the only format where the calculation changes based on whether you are betting on a favorite or an underdog.
Positive (+) American Odds — Underdog
The number tells you how much profit a $100 bet produces.
Profit = Stake × (Odds ÷ 100)
Total Payout = Stake + Profit
| Stake | Odds | Profit | Total Payout |
|---|---|---|---|
| $50 | +150 | $75.00 | $125.00 |
| $20 | +250 | $50.00 | $70.00 |
| $10 | +300 | $30.00 | $40.00 |
Mental shortcut: drop the plus sign, move the decimal two places left, and that is your profit multiplier. +150 → 1.50 × stake = profit. For a full breakdown, see our +150 odds explained guide.
Negative (−) American Odds — Favorite
The number tells you how much you must risk to win $100 profit.
Profit = Stake × (100 ÷ |Odds|)
Total Payout = Stake + Profit
| Stake | Odds | Profit | Total Payout |
|---|---|---|---|
| $75 | −150 | $50.00 | $125.00 |
| $55 | −110 | $50.00 | $105.00 |
| $100 | −200 | $50.00 | $150.00 |
| $30 | −300 | $10.00 | $40.00 |
Notice the pattern: at −110 (the standard line), $55 wins $50. At −200, you must risk double your profit. At −300, you risk triple. The bigger the negative number, the heavier the favorite and the smaller your return relative to what you risk.
Common question: “What does −110 pay on a $50 bet?” Profit = $50 × (100 ÷ 110) = $45.45. Total payout = $95.45. This is the most common line in sports betting — the standard vig on spreads and totals.
Fractional Odds: The UK/Ireland Format
Fractional odds (used in horse racing and UK sportsbooks) express profit as a ratio. The numerator is your profit; the denominator is the amount you bet.
Profit = Stake × (Numerator ÷ Denominator)
Total Payout = Stake + Profit
| Stake | Odds | Profit | Total Payout |
|---|---|---|---|
| $50 | 3/2 | $75.00 | $125.00 |
| $10 | 5/1 | $50.00 | $60.00 |
| $20 | 7/4 | $35.00 | $55.00 |
| $100 | 1/2 | $50.00 | $150.00 |
When the numerator is larger than the denominator (like 5/1 or 3/2), you are betting on an underdog. When it is smaller (like 1/2), you are betting on a favorite. The special case 1/1 is “evens” — you win exactly your stake as profit. See our evens guide for details. For deeper conversion examples, see the complete odds conversion guide.
All Formats Side by Side
The same bet expressed in all three formats always produces the same payout. Here is a $50 bet at equivalent odds across formats:
| American | Decimal | Fractional | $50 Profit | $50 Total Payout |
|---|---|---|---|---|
| −200 | 1.50 | 1/2 | $25.00 | $75.00 |
| −110 | 1.91 | 10/11 | $45.45 | $95.45 |
| +100 | 2.00 | 1/1 | $50.00 | $100.00 |
| +150 | 2.50 | 3/2 | $75.00 | $125.00 |
| +300 | 4.00 | 3/1 | $150.00 | $200.00 |
The highlighted row (+100 / 2.00 / 1/1) is even money — you win exactly what you risk. Everything above it is underdog territory (profit exceeds risk); everything below is favorite territory (risk exceeds profit). Use our Odds Converter or Decimal ↔ Fractional Converter to switch between formats instantly.
How to Calculate Parlay Payouts
A parlay combines multiple bets into one — all legs must win for the bet to pay. The payout is calculated by multiplying the Decimal odds of each leg together.
Step 1: Convert each leg to Decimal odds (if not already).
Step 2: Multiply all Decimal odds together = Combined Decimal.
Step 3: Total Payout = Stake × Combined Decimal.
Example — 3-leg parlay, $10 stake:
Leg 1: +150 = 2.50 Decimal. Leg 2: −110 = 1.91 Decimal. Leg 3: +200 = 3.00 Decimal.
Combined: 2.50 × 1.91 × 3.00 = 14.33. Total payout: $10 × 14.33 = $143.25 ($133.25 profit).
This is why parlays are popular — they turn small stakes into large payouts. But all legs must hit. If any one leg loses, the entire bet loses. The combined implied probability is the product of individual probabilities, making parlays extremely difficult to win. The house edge on a parlay is also compounded — each leg’s vig multiplies together, meaning the bookmaker’s total margin grows with each added leg.
How to Calculate the Bookmaker’s Margin
Knowing how to calculate the bookmaker’s margin tells you how much of your money goes to the house before you even place a bet. Here is the method:
Step 1: Convert each side to implied probability.
Step 2: Add them up. The excess above 100% is the margin.
Example: Lakers +150 / Celtics −200.
+150 implied probability: 100 ÷ 250 × 100 = 40.0%. −200 implied probability: 200 ÷ 300 × 100 = 66.7%. Total: 106.7%. Margin: 6.7%.
This means roughly 6.7 cents of every dollar wagered goes to the sportsbook. For comparison, a standard −110/−110 spread bet has a margin of about 4.8%, while heavy favorites can push margins above 10%. Shopping for the best odds across multiple sportsbooks is the simplest way to reduce the margin you pay. Our Margin Calculator automates this calculation for any market.
Formula Summary
Every formula in one place:
| Format | Profit Formula | Total Payout Formula |
|---|---|---|
| Decimal | (Stake × Odds) − Stake | Stake × Odds |
| American (+) | Stake × (Odds ÷ 100) | Stake + Profit |
| American (−) | Stake × (100 ÷ |Odds|) | Stake + Profit |
| Fractional (N/D) | Stake × (N ÷ D) | Stake + Profit |
| Parlay | (Stake × Product of Decimal Odds) − Stake | Stake × Product of Decimal Odds |
For all formats: Total Payout = Profit + Stake. That relationship never changes.
Related Tools and Guides
- Odds Converter & Payout Calculator — calculate payouts and convert between formats instantly
- Decimal ↔ Fractional Odds Converter — quick conversion for non-American formats
- Margin Calculator — calculate the bookmaker’s vig on any market
- What Does +150 Mean? — American odds explained in detail
- What Does Evens Mean? — even money (1/1, 2.00, +100) explained
- Betting Odds Conversion Guide — complete conversion formulas and history
- How to Calculate Gambling — EV, house edge, ROI, and session cost formulas