The Bet Builder (also known as Same Game Multi or SGM) has revolutionized football betting. It allows you to combine multiple markets from a single match—like “Man Utd to Win,” “Rashford to Score,” and “Over 9 Corners”—into one big wager.
However, there is a catch. Unlike standard accumulators where you simply multiply the odds, Bet Builders are subject to a “Correlation Tax.” If events are related (e.g., a team winning and their striker scoring), bookmakers drastically reduce the odds. Our Bet Builder Calculator helps you estimate this reduction, allowing you to see the difference between a standard mathematical parlay and the actual price you are getting.
Bet Builder Estimator
SGM CalcEstimate the real odds of a Same Game Multi by adjusting for the correlation between your selections.
* This is an estimation. Bookmaker algorithms vary.
How to Use the Bet Builder Calculator
This tool acts as a “Price Check” for your multis. Since bookmaker algorithms are secret, use this to estimate the fair value of your combination:
- Add Your Selections: Input the decimal odds for each leg of your bet. You can find these odds in the single markets (e.g., standard 1X2 odds or Over/Under odds).
- Set the Correlation (Crucial Step): Use the slider to estimate how related these events are.
- Low (0-20%): Events that don’t really affect each other (e.g., “Home Win” and “Total Corners”).
- High (40-60%): Events that are tightly linked (e.g., “Home Win” and “Home Team to Score in Both Halves”).
- Calculate: The tool will show you two numbers:
- Standard Acca: The odds if the events were independent (too high).
- Bet Builder Price: The estimated odds after the “Correlation Tax” is applied.
Understanding Correlation: The “Tax” on Your Odds
Why do bookies slash the odds? Because if one part of your bet wins, the other part becomes much more likely to win, reducing the bookie’s risk.
Example 1: High Correlation (The “Taxed” Bet)
You want to bet on Liverpool to Win (1.60) and Mo Salah to Score (2.00).
- Standard Math: $1.60 \times 2.00 = 3.20$.
- Reality: If Salah scores, Liverpool is highly likely to win. These events are not independent.
- Calculator Setting: Set correlation to High.
- Estimated Odds: ~2.20 to 2.40.
You lose almost 1.00 in value because the events overlap. This is where the calculator saves you from expecting a 3.20 payout.
Example 2: Low Correlation (The Value Bet)
You bet on Arsenal to Win (1.80) and Under 3.5 Cards (1.90).
- Standard Math: $1.80 \times 1.90 = 3.42$.
- Reality: A team winning doesn’t necessarily mean there will be few cards. In fact, winning teams often time-waste and get cards late on. The correlation is low.
- Calculator Setting: Set correlation to Low.
- Estimated Odds: ~3.20.
In this scenario, your Bet Builder price stays much closer to the true mathematical accumulator price.
Tip: To find the best odds for individual legs like “Both Teams To Score,” use our BTTS Calculator before building your bet.
Frequently Asked Questions (FAQ)
What is the difference between an Accumulator and a Bet Builder?
An Accumulator (Acca) combines selections from different matches (e.g., Man Utd to win AND Chelsea to win). Since the matches don’t affect each other, the odds are simply multiplied. A Bet Builder combines selections from the same match. Since events within one game affect each other, the odds are adjusted using complex algorithms.
Why are my Bet Builder odds lower than calculated?
This is due to Correlation. If you bet on outcomes that support each other (e.g., “Over 2.5 Goals” and “BTTS Yes”), the bookmaker reduces the payout because predicting one effectively predicts the other.
Can I use this calculator for real payouts?
This tool is an estimator. Every bookmaker (Bet365, FanDuel, DraftKings) uses a proprietary “black box” algorithm to price correlation. No external calculator can match it 100%, but this tool gives you a realistic baseline to verify if you are getting a fair price.
What is “Anti-Correlation”?
This happens when you bet on conflicting events, like “Under 0.5 Goals” and “Home Team to Win.” Most bookmakers block these bets, but if allowed, the odds would be astronomical because the events contradict each other.