Decimal odds show total return per 1 unit staked
Fractional odds show profit relative to stake
American odds show how much you win on a 100-unit stake or how much you must stake to win 100 units
Positive American odds indicate underdogs
Negative American odds indicate favorites
Higher decimal odds mean lower implied probability
Lower decimal odds mean higher implied probability
Fractional odds with a larger numerator relative to denominator mean lower implied probability
Implied probability can be estimated from odds
Decimal odds implied probability equals 1 divided by the decimal odds
Fractional odds implied probability equals denominator divided by numerator plus denominator
Positive American odds implied probability equals 100 divided by odds plus 100
Negative American odds implied probability equals odds absolute value divided by odds absolute value plus 100
Payout equals stake multiplied by decimal odds
Profit equals payout minus stake
Compare odds across books to find the best price
Check whether the odds are for the full result or a specific market
Verify whether odds are fixed, live, or subject to change