Betting Calculators
Free, instant calculators for every UK bet type. Singles, each-way, multiples and full-cover system bets like Lucky 15, Yankee and Heinz — plus an odds converter covering fractional, decimal and American formats.
Featured
Bet Calculator (all bet types)
One calculator covering every bet type. Switch between single, each-way, accumulator and full-cover system bets without leaving the page.
Singles
Multiples
Full-cover system bets
Every k-fold combination from your selections, bundled into one bet. The “Lucky” family includes singles too — the others start at doubles.
Trixie
3 selections, 4 bets — 3 doubles plus 1 treble. Two winners pays out.
Open calculatorPatent
3 selections, 7 bets — 3 singles + 3 doubles + 1 treble. One winner pays.
Open calculatorYankee
4 selections, 11 bets — 6 doubles + 4 trebles + 1 fourfold. Two winners pays out.
Open calculatorSuper Yankee (Canadian)
5 selections, 26 bets — 10 doubles + 10 trebles + 5 fourfolds + 1 fivefold.
Open calculatorLucky 15
4 selections, 15 bets — 4 singles + 6 doubles + 4 trebles + 1 fourfold. One winner pays.
Open calculatorLucky 31
5 selections, 31 bets including singles. One winner pays out.
Open calculatorLucky 63
6 selections, 63 bets including singles. One winner pays out.
Open calculatorHeinz
6 selections, 57 bets across doubles, trebles, fourfolds, fivefolds and a sixfold.
Open calculatorSuper Heinz
7 selections, 120 bets across doubles up to a sevenfold.
Open calculatorGoliath
8 selections, 247 bets across doubles up to an eightfold.
Open calculatorSettlement & pricing
Adjust an existing bet for non-runners (Rule 4), extract guaranteed value from a free bet, or work out exchange lay liability.
Rule 4 Calculator
Adjust your bet's price after a non-runner is withdrawn from the race.
Open calculatorFree-Bet ROI Calculator
Lock in guaranteed value from a stake-not-returned free bet by laying it on an exchange.
Open calculatorLay Calculator
Exchange-style — work out your liability, commission and outcomes when laying a bet.
Open calculatorRace day
Find runners across today's cards and check which bookmakers run BOG.
Utilities
Odds-format conversion, target-price reverse calc, and value-bet probability comparisons.
Odds Converter (Fractional ⇄ Decimal ⇄ American)
Convert between fractional, decimal and American odds instantly. See implied probability and bet returns.
Open calculatorRequired Odds Calculator
Reverse the calculator — start with the return you want and find the odds you need.
Open calculatorImplied Probability Comparator
Spot value bets by comparing your own probability estimate to the bookmaker's price.
Open calculatorOverround Calculator
Work out the bookmaker's margin from a race's prices: the book percentage, overround and fair odds.
Open calculatorKelly Criterion Calculator
Work out the optimal stake from your edge — full, half or quarter Kelly.
Open calculatorDutching Calculator
Split one stake across several runners for the same return whichever wins.
Open calculatorFrom the AI Lab
Understand the numbers behind the bets
A calculator gives you the maths. The AI Lab shows you the why — the bookmaker's margin baked into every price, how often each price actually wins, and whether any betting system beats it. Research, not tips.
Gamble Responsibly
Gambling should be entertaining and not seen as a way to make money. Never bet more than you can afford to lose. If you or someone you know has a gambling problem, help and support is available.