Value Tools

Convert odds, strip the vig, and check whether a bet has positive expected value.

Odds Converter

American ↔ decimal ↔ implied probability.

American odds (e.g. -150 or +130)

No-Vig Fair Odds

Enter both sides of a moneyline to remove the book's margin.

Side 1 odds (e.g. -150)

Side 2 odds (e.g. +130)

Expected Value

Compare your win probability against the offered odds.

Your estimated win probability (%)

Offered American odds

Stake ($)

Kelly Criterion

Bet sizing from edge and odds. Most bettors use a fraction (¼–½) of full Kelly to reduce variance.

Your estimated win probability (%)

Offered American odds

Bankroll ($)

How to use these together: take the no-vig fair probability from the odds board as the market's opinion. If your own estimate (from stats, pitching matchups, etc.) beats it, run the EV tool. Only when EV is positive does bet sizing (Kelly) even matter.