Betting calculators: odds, margin, hedge, Kelly

Five small calculators for the maths behind value betting. Pick one, type your odds and read the result.

Implied probability calculatorConvert decimal odds into the implied probability in percent. Type the odds and see the chance the bookmaker is pricing in.
No-vig fair odds calculatorRemove the bookmaker margin from a 2-way or 3-way market and get fair odds with both the multiplicative and the power method.
Hedge bet calculatorFind the stake that locks in the same payout on both sides after you placed a bet. See the locked result and the profit you give up.
Arbitrage stake calculatorSplit a total stake across the outcomes of a 2-way or 3-way arbitrage so every result pays the same. Shows profit and ROI.
Kelly criterion stake calculatorWork out the Kelly stake from the odds, your win probability and your bankroll. Pick full, half, third or quarter Kelly.

Put it into practice

kefas continuously collects odds from Lithuanian bookmakers and shows the highest price on offer for every pick.

Betting always carries risk: even a positive-EV bet can lose. Only stake what you can afford to lose, and if gambling is becoming a problem, seek help.