How do I use a sports betting odds calculator?

Enter your bet amount and the odds (American, Decimal, or Fractional format) into the calculator. It will instantly show your potential payout and profit. Our free sports betting odds calculator works for all sports including NFL football, NBA basketball, and MLB baseball.

How do I convert American odds to decimal odds?

For positive American odds: Decimal = (American/100) + 1. For negative American odds: Decimal = (100/|American|) + 1. For example, +150 American = 2.50 Decimal, and -150 American = 1.67 Decimal. Use our free odds converter for instant conversions.

What is the best free parlay calculator?

SportsBettingOddsCalculator.com offers the best free parlay calculator online. Enter up to 15 legs with American, Decimal, or Fractional odds to instantly calculate your total parlay payout and implied probability.

How do I calculate my betting payout?

Use our bet payout calculator: enter your stake and odds. For American odds, if positive: Payout = Stake × (Odds/100) + Stake. If negative: Payout = Stake × (100/|Odds|) + Stake. Our calculator does this instantly for any odds format.

What is an odds payout chart?

An odds payout chart shows potential winnings at different odds levels. Our calculators provide dynamic payout charts for any stake amount, showing payouts for common odds like -110, +100, +150, -200, and more.

Risk of Ruin Calculator

Calculate your probability of losing your entire bankroll based on win rate, odds, and unit size. Essential for proper bankroll management and understanding betting risk.

Your Betting Profile

Enter your bankroll and betting parameters

Bankroll ($)

Unit Size ($)

2.0% of bankroll

Win Rate (%)

Average Odds

Ruin Threshold ($)

Amount at which you'd stop betting (default: $0)

Risk Analysis

Risk of Ruin Guide

Very Low

< 1%

Professional-level risk management

Low

1-5%

Conservative, sustainable approach

Moderate

5-20%

Acceptable for experienced bettors

High

> 20%

Reduce unit size or improve edge

Understanding Risk of Ruin

Risk of Ruin (RoR) is the probability that you will lose your entire bankroll before achieving your goals. Even profitable bettors with a positive edge can go broke if they bet too large relative to their bankroll - this is why proper bankroll management is crucial.

The Math Behind Risk of Ruin

Risk of Ruin depends on three main factors: your edge (expected profit per bet), your unit size (bet size relative to bankroll), and variance (how much results fluctuate). A larger edge and smaller units both reduce RoR, while high variance increases it.

Kelly Criterion Explained

The Kelly Criterion is a formula that calculates the optimal bet size to maximize long-term bankroll growth. However, full Kelly is aggressive and comes with significant drawdowns. Most professional bettors use Half Kelly or Quarter Kelly to reduce volatility while still growing their bankroll efficiently.

Practical Guidelines

Never bet more than 5% of bankroll: Even with a huge edge, large units create ruin risk
1-2% is standard: Most successful bettors use 1-2% unit sizes
Account for variance: Higher odds bets need smaller unit sizes
Recalculate regularly: Adjust units as your bankroll changes
Have a stop-loss: Set a ruin threshold above $0 for mental health

This calculator is for informational and educational purposes only. Results should be verified with your sportsbook before placing any wagers. All betting carries risk. Full Disclaimer