The same math sharp bettors use to size bets, find +EV, and measure sportsbook margins. Pick a tool — every calculator is free, with no signup.
Find out if a bet is +EV before you place it. Plug in odds and your win probability — get the dollar EV, ROI, and breakeven win rate.
Optimal bet sizing for long-term growth. Enter your bankroll, win probability, and odds — get Full, Half, and Quarter Kelly stakes side by side.
How much edge does the book bake into a market? Enter both sides of a line and see the hold percentage instantly.
Strip the juice. Enter both sides of a market — get the no-vig fair odds and true implied probability for each side.
Convert between American, Decimal, Fractional, and Implied Probability in real time. Edit any format, the others update.
What win rate do these odds require? Convert odds into the implied probability you'd need to break even.
Add legs, see the combined odds and payout. Works with American, decimal, or implied probability inputs.
Same legs, two strategies. See whether parlaying or straight-betting wins more bankroll long-term — and how the variance compares.
Pick'em / DFS contest math. See the breakeven hit rate per pick and whether your slip is +EV at the platform's payout multipliers.
Project where your bankroll lands. Pick a stake strategy, edge, and number of bets — see the expected growth curve and variance.