The “Bet Builder” (also known as Same Game Parlay or SGP) has revolutionized sports betting. It allows you to combine multiple outcomes from a single match—like “Arsenal to Win” AND “Saka to Score”—into one big wager.
However, calculating the odds for these bets is not as simple as multiplying the numbers. Because the events are often related (correlated), bookmakers apply a “correlation tax” that reduces the total odds. Our Sports Bet Builder Calculator allows you to build your virtual betting slip and instantly see the estimated payout for both standard parlays and complex SGPs.
Bet Slip Builder
To calculate the exact fair value based on correlation, use our SGP Correlation Tool.
How to Use the Bet Builder Calculator
This tool mimics the interface of a sportsbook betting slip, allowing you to experiment with different combinations before placing real money.
- Add Selections: Click “Add Selection” for every leg of your bet. Enter the name (optional) and the decimal odds.
- Enter Stake: Input the amount you plan to wager in the “Stake Amount” box.
- Choose Your Mode:
- Standard Mode (Toggle OFF): Use this for accumulators involving different matches (e.g., Man City to win, Lakers to win, Djokovic to win). The odds are multiplied simply.
- Same Game Parlay Mode (Toggle ON): Use this if all your selections are from the same match. The calculator will apply an algorithm to simulate the bookmaker’s payout reduction.
- Check Returns: See your Total Odds and Potential Return instantly.
Related Tools: If you want to understand the exact mathematical correlation between two specific events (and find fair value), use our advanced SGP Correlation Calculator. For simple multi-game bets without SGP logic, you can also use our standard Parlay Calculator.
Understanding SGP Logic: Why Odds Change
The most common question bettors ask is: “Why is my payout lower when I combine bets from the same game?”
Example 1: The Independent Parlay (Standard)
You bet on three separate events that have nothing to do with each other:
- Real Madrid to Win (1.50)
- Kansas City Chiefs to Win (1.40)
- Novak Djokovic to Win (1.80)
Calculation: 1.50 × 1.40 × 1.80 = 3.78 Total Odds.
Since the events are independent, the math is straightforward.
Example 2: The Same Game Parlay (SGP)
You build a ticket for a single Liverpool match:
- Liverpool to Win (1.50)
- Liverpool Over 1.5 Goals (1.20)
If you simply multiplied these (1.50 × 1.20), you would get odds of 1.80. However, this is wrong.
If Liverpool wins, they must have scored goals. These events are highly correlated. The bookmaker knows this and will reduce the odds, offering you something closer to 1.55 or 1.60. Our calculator’s “SGP Mode” simulates this reduction to give you a realistic estimate of what the sportsbook will offer.
Frequently Asked Questions (FAQ)
What is a Same Game Parlay (SGP)?
An SGP is a bet that combines multiple selections from a single sporting event into one wager. All selections must win for the bet to payout. It is also known as a “Bet Builder” (UK/Europe) or “One Game Parlay.”
Why are Bet Builder odds lower than standard Parlay odds?
Because the outcomes are often correlated. If you bet on a Quarterback to throw 3 touchdowns and his team to win, the events support each other. Bookmakers reduce the payout to account for this increased probability. If they didn’t, they would lose money rapidly.
Can I combine multiple Bet Builders?
Yes, this is often called a “Bet Builder Plus” or “SGPx”. You can create a Bet Builder for Match A, another for Match B, and combine them into a single accumulator. To calculate this, turn “SGP Mode” OFF and simply enter the final odds of each individual Bet Builder as a single selection.