Betting Tools

Ten calculators for thinking in probability.

A focused toolkit for understanding how sports markets price events. Everything runs locally - no accounts, no tracking, no picks for sale.

Translate American, Decimal, and Fractional odds with implied probability side-by-side.

Convert any price into the probability the sportsbook is quoting.

Combine legs to see the true combined odds, payout, and implied probability.

Translate your bankroll into rational unit sizes using flat or Kelly sizing.

Compare your estimated true probability against market odds to see edge per bet.

How much a winning stake returns at any American or decimal price.

Track a session of bets locally and see net units, ROI, and hit rate.

Paste a price history and plot how a market moved over time.

Model long-run return on investment from your win rate and average odds.

Compare two probability estimates and translate the gap into a fair-odds delta.