Convert odds to implied probability
Implied probability is the percentage represented by a quoted price. It is a property of the odds, not a forecast that the outcome will happen.
Formula and worked example
Implied probability = 1 / Decimal odds
Decimal odds of 2.50 imply a probability of 1 / 2.50 = 0.40, or 40%. Fractional odds of 3/2 and American odds of +150 represent the same price.
Why this is not a no-vig probability
A single implied probability does not reveal the bookmaker margin. You need the prices for every mutually exclusive outcome, add their implied probabilities, then normalise each one against that total. Use the vig calculator for that market-wide calculation.
Limits and responsible use
The result does not predict the outcome and does not account for settlement rules. UK-licensed operators must publish rules covering voids, errors, withdrawals and maximum payouts. 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, 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.