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How to Calculate Your Bowling Handicap — Step-by-Step Guide

Learn how to calculate your bowling handicap using the USBC formula. Covers averaging your scores, applying the basis average, percentage factor, and finding your adjusted score.

Calculating your bowling handicap takes three steps: find your average, subtract it from the basis average, and multiply by the percentage factor. The result — always rounded down to a whole number — is added to your raw game score for competition.

Skip the math with our Bowling Handicap Calculator.


The USBC Handicap Formula

Handicap = floor((Basis Average − Your Average) × Percentage Factor)

  • Basis Average — A fixed number set by your league, typically 200, 210, or 220
  • Your Average — The floor of your average score across your recent games
  • Percentage Factor — Usually 90% in USBC leagues; sometimes 80% or 100%
  • floor() — Always drop the decimal fraction, never round up

Step 1: Calculate Your Bowling Average

Add all your game scores together, divide by the number of games, and drop the fraction.

Formula: Average = floor(sum ÷ number of games)

Example: You bowled 157, 143, and 142 in your last three league games.

  1. Sum: 157 + 143 + 142 = 442
  2. Divide: 442 ÷ 3 = 147.33…
  3. Drop the fraction: average = 147

Always use floor (drop the fraction), not standard rounding. 147.9 becomes 147, not 148.


Step 2: Apply the Handicap Formula

Subtract your average from the basis average and multiply by the percentage factor.

Example (continued): Basis average = 200, percentage factor = 90%

  1. Difference: 200 − 147 = 53
  2. Multiply: 53 × 0.90 = 47.7
  3. Drop the fraction: handicap = 47

Step 3: Find Your Adjusted Score

Add your handicap to your raw game score.

Example: You bowl 143 tonight.

  • Adjusted score = 143 + 47 = 190

This 190 is the number used in the league standings — not the raw 143.


Full Example Table

VariableValue
Game scores157, 143, 142
Averagefloor(442 ÷ 3) = 147
Basis average200
Percentage factor90%
Difference200 − 147 = 53
Before floor53 × 0.90 = 47.7
Handicap47
Tonight's raw score143
Adjusted score190

What Basis Average and Percentage Factor Should I Use?

Your league officials set these. Common combinations:

Basis AveragePercentage FactorTypical League Type
20090%Most recreational USBC leagues
21090%Intermediate / mixed leagues
22090%Competitive / higher-average leagues
20080%Leagues that want skill to play a larger role
200100%Maximum equalization leagues

If you are bowling informally with friends, 200 and 90% is a practical starting point agreed upon by most casual bowlers.


When Is Your Handicap 0?

If your average is equal to or greater than the basis average, the formula returns zero (or a negative number which is floored to zero). You bowl on scratch — raw score only, no adjustment.

Example: Average = 205, basis = 200 → (200 − 205) = −5 → floor = 0


How Often Does My Handicap Change?

In a formal league, your handicap is recalculated each week (or session) as your running average changes. Early in a season, the average is based on fewer games and may shift more noticeably. By mid-season, the average stabilizes and handicap changes become smaller.


Disclaimer: Information provided by this site is for educational purposes only and is not intended to be a substitute for professional medical advice specific to the reader's particular situation. The information is not to be used for diagnosing or treating any health concerns you may have. The reader is advised to seek prompt professional medical advice from a doctor or other healthcare practitioner about any health question, symptom, treatment, disease, or medical condition.