SGP Correlation Calculator

1. Pick a Mode: Check Book Price (compare a posted SGP to fair) or Build Fair Price (construct it from legs).
2. Pick odds formats, enter each leg's Fair Odds, and set the Correlation (Positive, Neutral, or Negative preset, or tune the matrix).
3. Enter the Book SGP Price (Check mode) and a Stake.
4. Read the output. Fair SGP Price, EV $ / %, and Expected Payout.

What is an SGP correlation calculator?

An SGP correlation calculator analyzes the pricing of same game parlays in two complementary ways. In Check Book Price mode, the calculator compares a sportsbook's offered SGP price against an independently calculated fair price to determine whether the SGP is +EV or -EV. In Build Fair Price mode, the calculator constructs a fair price from the individual leg odds and a chosen correlation assumption.

A same game parlay (SGP) is a parlay made entirely of legs from the same game. Unlike a traditional parlay built from independent events, SGP legs are often correlated. A quarterback's passing yards and the team's total points are positively correlated. A team's spread and total points can be either positively or negatively correlated depending on game script.

Correlation presets and the matrix

The calculator offers three correlation presets (Positive, Neutral, Negative) for fast analysis. Power users can tune the correlation matrix directly to model specific relationships between legs. A correlation factor less than 1 indicates positive correlation (legs more likely to all win together). Greater than 1 indicates negative correlation.

Worked example (Check Book Price)

Three legs at -110, +120, and -150 as straight bets convert to decimals 1.91, 2.20, 1.67.

The book is pricing positive correlation: the legs are 22% more likely to all hit together than independence would suggest. The bettor can now decide whether the book's correlation estimate is reasonable.

Why SGP correlation matters for sports bettors

Identifying mispriced correlation is one of the few ways a sharp bettor can find edge in retail sportsbook SGPs. If the bettor's model of correlation disagrees with the book's implied correlation, the SGP may be +EV or -EV depending on the direction of the disagreement.

This calculator does not tell the bettor whether the book's correlation estimate is right. It tells the bettor what the book's estimate is. Comparing that estimate to independent analysis is where edge comes from.

SGP correlation analysis builds on parlay math. For the foundational walkthrough, read our What is a Parlay guide. Pair this calculator with the Parlay Calculator for straight parlay math.

Common mistakes

• Assuming independent correlation in the baseline. If two legs are obviously correlated (Mahomes passing TDs and Chiefs winning), starting from an independent baseline is the right way to back out the book's adjustment, but it is not the right way to estimate true probability. Both numbers matter.
• Confusing correlation with edge. Identifying the book's implied correlation does not tell you whether the SGP is +EV. You need an independent view of true correlation to make that judgment.
• Reading the sign incorrectly. When the book's SGP price is lower than independent, the book is acknowledging positive correlation. When it is higher, the book is acknowledging negative correlation. The calculator labels this for you, but the math sign convention can confuse first-time users.
• Treating every SGP as inefficient. Sportsbooks have invested heavily in correlation modeling. Most SGPs are priced approximately correctly. Look for outliers, not assume every SGP is mispriced.