← Free tools

Odds converter

American, decimal, fractional and implied probability — instantly.

American

-110

Decimal

1.91

Fractional

10/11

Implied win %

52.38%

Choose the format you’re entering, then read the rest. Implied win % includes the book’s margin (the vig).

American, decimal, fractional — what’s the difference?

American odds use + and − (e.g. +150 means $150 profit on a $100 bet; −110 means you risk $110 to win $100). Decimal odds (common in Canada and Europe) show your total return per $1 staked (1.91). Fractional odds (UK) show profit relative to stake (10/11).

The implied probability is the win rate the odds bake in — including the book’s margin (the “vig”). Comparing that implied probability to your own estimate is the heart of finding value. Bankroll Guardian de-vigs and tracks this automatically for every bet you log.

Track every bet automatically

Stop doing the math by hand. Bankroll Guardian logs your bets and shows P&L, ROI, CLV and more — free to start, no card required.