Betting calculators
Free betting calculators that work with decimal, American and fractional odds: strip the vig out of a market, convert prices, price a parlay, hedge a bet or size a stake. Each one shows its maths, so you can check the book.
- Any odds format
- No sign-up
- Runs in your browser
Price tools
Every price hides a chance and a cut. These three show you both, so you can compare a line across books on equal terms.
No-vig calculator
Strip the bookmaker margin out of a market and see the fair odds.
Odds converter
Switch any price between decimal, American and fractional.
Implied probability calculator
Turn a price into the chance it implies, or a chance into a price.
Staking tools
Once you know the price, the question is how much. These work out parlay payouts, hedge stakes and Kelly sizing in a few taps.
Parlay calculator
Combined odds and payout for up to ten legs, plus the stacked margin.
Hedge calculator
Back the other side to lock in a result on a bet you already placed.
Kelly calculator
Size a stake from your own win chance and the price on offer.
Why we built these
We measure the margin on every sportsbook we review, and the same maths sits behind these calculators. The no-vig calculator uses the definition from our reviews, so a market you check here compares straight with the margins in our tables.
The tools give you numbers, not picks. A fair price or a Kelly stake is only as good as the estimate you feed it, and betting stays paid entertainment, never income. How betting margin works · Bet with limits