How to use the GFR Calculator
The GFR calculator estimates kidney filtration (eGFR) from age, sex and blood creatinine using the CKD-EPI 2021 equation.
What you need to enter
- Sex
- Age
- Serum creatinine (mg/dL)
The formula
eGFR = 142 × min(Scr ÷ κ, 1)^α × max(Scr ÷ κ, 1)^−1.200 × 0.9938^age × 1.012 (if female).
Worked example
Using the default values in the calculator:
- Sex: Male
- Age: 50
- Serum creatinine (mg/dL): 1
| eGFR | 92 mL/min/1.73 m² |
| Stage | G1 (normal or high) |
Tips for better results
- Only a clinician can interpret results.
- Muscle mass and diet affect creatinine.
Common mistakes to avoid
- Self-diagnosing.
- Using one result without repeat tests.
Please note: Health calculators and guides give general estimates, not medical advice. Talk to a doctor or other qualified professional about your own health. See our Disclaimer.