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.

March Madness Bracket Calculator

Calculate NCAA Tournament bracket probabilities, upset rates, and betting value using historical seed data from 1985-2024.

Favorite Seed

Underdog Seed

Favorite Moneyline Odds

Enter American odds (e.g., -2000 for heavy favorite)

Historical Upset Rate

0.6%

#16 beats #1 historically

Implied Probability

4.8%

Market implied underdog win rate

Betting Value Analysis

Value on Underdog (#16)-4.2%

Value on Favorite (#1)+4.2%

Historical Advancement Rates

Seed	R64	R32	S16	E8	F4	Final
#1	99.4%	87.5%	68.8%	50%	37.5%	25%
#16	0.6%	0.2%	0.05%	0.02%	0.01%	0.005%

Historical data based on NCAA Tournament games from 1985-2024. Individual game outcomes depend on many factors including team strength, injuries, and matchup specifics.

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

How to Use This Calculator

1
Select Seeds: Choose the favorite and underdog seed numbers for the matchup.
2
Enter Odds: Input the current moneyline odds on the favorite.
3
Analyze Value: Compare implied probability to historical upset rates to find betting value.
4
Check Advancement: View each seed's historical advancement rates by round.

Frequently Asked Questions

How accurate are historical upset rates?

Historical upset rates are based on every NCAA Tournament game from 1985-2024 (nearly 40 years of data). While past performance doesn't guarantee future results, these rates provide a solid baseline for expected outcomes.

What's the most common upset in March Madness?

The 12 vs 5 matchup is the most famous upset spot, with 12 seeds winning about 35% of the time. The 11 vs 6 and 10 vs 7 matchups are also common upsets at 37-40%.

Has a 16 seed ever beaten a 1 seed?

Yes! UMBC defeated Virginia 74-54 in 2018, becoming the first 16 seed to beat a 1 seed in tournament history. In 2023, Fairleigh Dickinson also upset Purdue as a 16 seed.