Same Game Parlays are heavily marketed during NFL broadcasts, but they are also among the hardest bets to price correctly. NFL same-game props often feature stronger and more intuitive internal correlations than many mainstream betting markets, especially when QB-driven stats are involved.
Our NFL SGP Correlation Calculator estimates whether a Same Game Parlay is overpriced or roughly fair by adjusting independent-leg probabilities for correlation. NFL correlations are often stronger than NBA because quarterback performance drives multiple statistical outputs simultaneously.
What this tool does and does not do:
- Best for: 2-leg NFL SGP screening.
- Usable for 3 legs as a rough directional check.
- Beyond 3 legs: treat results as approximate only.
- You supply: fair probability per leg and a rough correlation estimate.
- Output: directional pricing check, not exact bookmaker replication.
NFL SGP Correlation Calculator
Same Game ParlayHow to Use the Calculator
- Add your legs: Enter a description, your fair probability (%), and the individual book odds for each leg.
- Select correlation: Choose the average pairwise correlation. See the NFL-specific reference table below.
- Enter SGP odds offered: The combined American odds the sportsbook gives for the parlay.
- Read results: Fair odds vs book odds side-by-side, combined probability (independent vs correlated), edge, EV per $100, and the price gap between your model and the book.
NFL Correlation Reference
NFL correlations tend to be stronger than NBA because a single player (the QB) drives multiple statistical outputs. Use these as starting ranges, not fixed values.
| Leg Pair | Typical r | Direction |
|---|---|---|
| QB Passing Yards + WR Receiving Yards (same team) | +0.25 to +0.40 | Strong positive — WR yardage is a direct component of QB yardage |
| QB Passing Yards + Team Total | +0.20 to +0.35 | Strong positive — passing drives scoring |
| QB Passing TDs + Team Total | +0.30 to +0.45 | Very strong — TDs are the primary scoring method |
| RB Rushing Yards + Team Win | +0.10 to +0.20 | Moderate — winning teams run more in the 4th quarter |
| QB Passing Yards + Game Total Over | +0.15 to +0.25 | Moderate — both QBs contribute to total |
| QB Passing Yards + RB Rushing Yards (same team) | -0.10 to -0.20 | Moderate negative — pass-heavy game scripts reduce rushing volume, and vice versa |
| Team Win + Opponent QB Passing Yards Over | +0.05 to +0.15 | Weak positive — losing QBs throw more in garbage time |
| RB Anytime TD + Team Total Over | +0.10 to +0.20 | Moderate — more TDs in high-scoring games |
| Player Anytime TD + Same Player Yards Over | +0.05 to +0.15 | Weak positive — higher volume increases both |
Why NFL SGP Correlations Are Stronger Than NBA
In the NBA, player stats are distributed across 5 starters and a rotation. No single player typically drives more than 25-30% of team output. In the NFL, the QB is central to multiple offensive outputs at once — passing yards, receiving yards for his targets, team total, and game total are all tightly linked through the same player. This means:
- QB Pass Yards + WR Rec Yards are essentially overlapping statistics — every receiving yard by a WR is also a passing yard for the QB. The correlation is very high (~0.30-0.40).
- QB Pass TDs + Team Total are closely linked — most team TDs come through the passing game. Correlation can be very strong in pass-heavy offenses.
- Game script amplifies everything. In a game where one team trails by 14, both QBs may exceed their yardage projections — the trailing team throws to catch up, and the leading team throws in response. This creates cross-team correlation that does not exist in NBA SGPs.
Sportsbooks do apply correlation adjustments to NFL SGPs through proprietary pricing engines, but those adjustments are opaque and may not always match a bettor’s own fair-value assumptions. The calculator helps you estimate what the fair combined price should be under your correlation assumption, so you can evaluate whether the offered SGP looks expensive or reasonable.
Worked Example
SGP: QB Over 249.5 passing yards (fair: 54%) + WR1 Over 64.5 receiving yards (fair: 52%). Book offers +210.
- Independent: 0.54 × 0.52 = 28.08%
- With r = 0.30 (QB + WR same team): ≈ 28.08% + 0.30 × sqrt(0.54 × 0.46 × 0.52 × 0.48) ≈ 35.5%
- Fair odds: 1 / 0.355 = 2.81 decimal = +181
- Book offers: +210 (implied 32.3%)
- Model gap: 35.5% – 32.3% = +3.2%
In this case, the offered SGP price is longer than the model-implied fair price, which may indicate a small model-based edge — potentially because the book’s correlation penalty is more aggressive than your estimate. However, a +3.2% gap is marginal given model uncertainty.
Limitations
- Single average r for all pairs. In reality, QB-WR correlation differs from RB-Team Total correlation. The calculator uses one uniform r as a simplification.
- First-order approximation. The Gaussian copula model is a rough adjustment, not a full multivariate probability model. Results are directional.
- Fréchet bounds applied. The combined probability is clamped to mathematically possible limits, but this does not guarantee accuracy within those bounds.
- NFL SGP margins vary widely. Some sportsbooks charge more for highly correlated legs; others apply minimal adjustment. Compare across books when possible.
- Your fair probabilities drive everything. If your per-leg probability estimates are off, the combined analysis is off.
Frequently Asked Questions (FAQ)
Because every receiving yard gained by the WR is also a passing yard for the QB. If the WR catches a 40-yard pass, both players gain 40 yards on that play. This mechanical overlap creates a correlation of 0.30-0.40, which is much higher than most NBA prop pairs.
Can I use this for cross-game parlays?
Cross-game parlays are often treated as approximately independent for practical betting math, unless the legs share a meaningful external driver (e.g., weather in the same stadium). For cross-game parlays, set r = 0.00 and the calculator reverts to standard parlay math.
Why would an SGP ever have positive EV?
Positive EV can come from several sources: one or more individual legs may be mispriced; the sportsbook’s correlation adjustment may be overly conservative (penalizing a pair more than warranted); or the SGP may be part of a promotional boost with artificially improved odds. In general, finding +EV SGPs without promotions is rare due to the high effective margins.