True odds (fair odds) are the prices that would be offered if a sportsbook took zero margin, reflecting the model's best estimate of an event's actual probability.
True Odds
**TL;DR:** True odds (fair odds) are the prices that would be offered if a sportsbook took zero margin, reflecting the model's best estimate of an event's actual probability.
What it means
Every posted odd is the true odd plus the operator's margin. If a fair model says Real Madrid beats Bayern with 60% probability (true decimal odds 1.667), the book might post 1.59 — embedding ~5% margin. True odds are also called "no-vig" or "no-juice" lines.
For sharps, the entire game is identifying selections where their estimate of true probability differs meaningfully from the book's implied probability. For operators, true-odds modelling is the foundation that determines whether posted prices are profitable.
Formula / How it's measured
To strip vig from a two-way market with decimal odds (A, B):
- Implied probA = 1/A, implied probB = 1/B
- Overround = implied probA + implied probB
- True probA = implied probA / overround
- True odds A = 1 / true probA
Example: Real Madrid 1.59, Bayern 2.40. ImpliedA = 0.629, ImpliedB = 0.417. Overround = 1.046 (4.6% margin). True probA = 0.629/1.046 = 0.601 → true odds 1.664. So fair Madrid price is ~1.66; book posted 1.59 with 4.6% vig.
Why it matters for operators
True-odds calculation is the foundation of trader judgement, line moves, sharp detection (does the player consistently beat true odds?), and margin reporting. CFO-level book P&L reconciliation depends on knowing how much of revenue came from true edge vs variance.
Common benchmarks (2026)
- Top operators target 90%+ true-odds modelling coverage on football
- True-odds models for niche sports (esports, table tennis): less mature, wider margins
- Margin layered on top of true odds: 3%–6% football, 6%–12% niche
- Closing-line true odds usage as benchmark: now standard in sharp detection
- Vendors: Sportradar MTS, Genius Sports, Betgenius, Stats Perform, proprietary
Common mistakes
- Treating competitor lines as true odds — circular reasoning
- Ignoring market-derived true odds (closing line is closest available proxy)
- Using static true-odds models that don't update intra-event
See also