Market Margin & RTP Checker
Two checks, one page. Market margin: enter all outcomes of a betting market (two-way, three-way, outright, correct score) and get the overround and fair odds. Payout table: enter a game's chances and payouts and get the real RTP. Recomputes as you type.
Market margin (betting)
All outcomes of ONE market - the moneyline pair, the 1/X/2 trio, every outright contender, every correct-score line. Odds in any format.
enter the market outcomes…
Payout table (casino originals)
Each outcome's chance and its TOTAL payout - catches in-house games whose advertised math does not add up.
enter the outcomes…
What the market margin tells you
The sum of implied probabilities above 100% IS the book's price: a two-way market at 102.83% keeps ~2.76% of everything wagered, a typical esports moneyline pair runs 106-108% (6-8% margin). Outrights and correct-score markets usually hide much bigger margins - this is the tool that exposes them. For a single odds conversion use the odds converter →
Total payout, not net win (payout table)
A standard dice win pays 2x total (your stake back plus the same again) at 49.5% chance - that is 99% RTP, 1% house edge. A "half your money back" outcome is 0.5x, your full stake back is 1x, a total loss is 0x. If a probability row is missing (say the house edge lives in a jackpot you ignored), the remaining chance is counted as a full loss - and says so.
What the payout table is good for
Checking unusual dice rules, variable multipliers and small in-house games against what they advertise: a 1% edge claim with a 48%/2x table is really 4% edge - this tool catches exactly that. For games whose outcome space you cannot enumerate, use the session-risk model instead.