Betting odds express how much a bet pays and the implied chance of it winning. Decimal odds (e.g. 2.50) show the total return per unit staked, and you convert them to an implied probability with 1 ÷ odds — so 2.50 implies a 40% chance.
Decimal, Fractional and American
Decimal (2.50) is total return per £1 staked. Fractional (3/2) is profit relative to stake. American (+150 / −200) is profit on a 100 stake, or the stake needed to win 100. Decimal is the easiest format for comparing value.
The Overround
Add up the implied probabilities of every outcome in a market and you will get more than 100%. That excess is the bookmaker’s margin — the “overround” or “vig”. The lower the overround, the better the price for you.
How TACTIX Applies This
TACTIX shows the model’s probability next to the market’s implied probability on every fixture, so you can see the margin and the edge at a glance. See the betting calculator and today’s value.
Frequently Asked Questions
How do I convert odds to a percentage?
Divide 1 by the decimal odds and multiply by 100. Odds of 4.0 imply 25%.
What is the overround?
The amount by which a market’s implied probabilities exceed 100% — the bookmaker’s built-in margin.
18+. Educational information, not betting advice. Please gamble responsibly — BeGambleAware.org.
This post is generated from TACTIX’s match data by our software and checked automatically. How it works →
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