Koff Expected Bladder Capacity
Koff expected bladder capacity (Koff 1983): (age in years + 2) × 30 mL.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Age
- 4
Result: Expected bladder capacity 180 mL for age 4 years ((4 + 2) × 30).
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Age (years)
How this is calculated
- Formula
- expected bladder capacity (mL) = (age in years + 2) × 30.
- Range
- the standard reference estimate for children roughly 1 to 12 years.
Koff SA. Estimating bladder capacity in children. Urology. 1983;21(3):248. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.