Calculate expected value
A value betting calculation compares the market's implied probability with an independent probability estimate. The output is only as reliable as the estimate you enter.
Formula and worked example
Expected value per unit = (Estimated probability x Decimal odds) - 1
Expected profit = Stake x Expected value per unit
Edge = Estimated probability - Implied probability
At odds of 1.95 and an estimated probability of 53.8462%, expected value is about +0.05 per unit. A stake of 20 therefore has an expected profit of about 1 under those inputs. This is a probability-weighted expectation, not the next result.
Interpreting edge and expected value
A positive result means your estimate is higher than the market-implied probability by enough to overcome the price. A negative result means the offered price is below the fair price implied by your estimate.
Review how you produced the estimate, account for market margin and track whether your assumptions remain calibrated. The vig calculator can normalise a full market before comparison.
Limits and responsible use
Expected value does not guarantee profit. Limits, price movement and operator settlement rules can change the available or realised result. See Gambling Commission LCCP 4.2.6.
Set a spending limit before gambling and do not chase losses. Read GambleAware's advice and our responsible gambling guidance.
Related tools and guides
After checking the price and risk, you can compare betting partners. Oddly Likely may earn a commission from partner links; check current odds, eligibility and terms. Read the affiliate disclosure.
Sources
- Gambling Commission, LCCP condition 4.2.6. Current code accessed 30 July 2026.
- GambleAware, Advice to consider if you're gambling. Accessed 30 July 2026.