There are more Sports Betting and Gambling tools located here.
Here’s a quick user guide for the Break-even Win Rate Calculator.
What it does
- Calculates the minimum hit rate (break-even win rate) you need to not lose money at a given price/odds.
- Supports Decimal, American, and Fractional odds.
- Optional commission/vig adjustment.
How to use
- Choose odds format
- Use the “Odds format” dropdown to match your price format:
- Decimal (e.g., 2.50)
- American (e.g., +150 or -120)
- Fractional (e.g., 5/2)
- Enter your odds/price
- Type the price exactly in the chosen format.
- Examples:
- Decimal: 1.80, 2.00, 2.50
- American: +150, -120
- Fractional: 5/2, 11/8, 1/1
- Optional: add commission/vig
- If your exchange/book charges a commission on winnings, enter it in “Commission/Vig %”.
- Leave blank or 0 if none.
- Choose precision
- Set how many decimal places you want in the results (0–6). Default is 2.
- Calculate
- Click “Calculate” to see results.
- Click “Reset” to clear all fields and start over.
Understanding the results
- Break-even hit rate: The minimum win percentage you must achieve at the given price (and commission, if any) to break even.
- Fair probability: Same value shown as a probability—your price implies this chance of winning.
- Fair price (decimal): The equivalent decimal odds at break-even. Use this to compare against quoted prices.
Quick examples
- Decimal 2.00 with no commission → Break-even 50.00%
- American +150 → Break-even 40.00%
- Fractional 5/2 → Break-even 28.57%
- Decimal 2.00 with 5% commission → Break-even > 50% (because your effective payout is reduced)
Common tips
- Make sure the odds format matches the input (e.g., don’t type “+150” while Decimal is selected).
- American odds must be integers (+150, -120), not decimals.
- Fractional odds use n/d with whole numbers (e.g., 5/2).
- If you see an error, check for typos or invalid values (e.g., Decimal must be > 1.00).


