eGFR Calculator
Estimate kidney function (eGFR) from a creatinine blood test, age and sex with the CKD-EPI 2021 equation, and see the chronic kidney disease stage.
eGFR
79 mL/min/1.73 m²
- Kidney function
- G2: mildly reduced
An eGFR of 79 is stage g2: mildly reduced.
How it's worked out
- Creatinine1.1 mg/dL
- CKD-EPI 2021
142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.2 × 0.9938^age79.3
- For adults only. A single result can be affected by dehydration, a meat meal or muscle mass; chronic kidney disease is diagnosed from results over at least 3 months, with urine tests. Discuss results with your doctor.
The equation
eGFR = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.2 × 0.9938^age × 1.012 (if female)
κ is 0.7 for women and 0.9 for men; α is −0.241 for women and −0.302 for men. Creatinine in µmol/L is divided by 88.42 first.
Worked example
A 55-year-old man with creatinine of 1.1 mg/dL (97 µmol/L) has an eGFR of about 79: stage G2, mildly reduced.
For adults only. Kidney disease is diagnosed from repeated tests over at least 3 months; talk to your doctor about any result.
Questions people ask
What is eGFR?
Estimated glomerular filtration rate: how well your kidneys filter blood, in mL per minute per 1.73 m². 90 or more is normal.
What do the stages mean?
G1 is 90 or more, G2 60 to 89, G3a 45 to 59, G3b 30 to 44, G4 15 to 29 and G5 below 15 (kidney failure).
Why doesn't it ask about race?
The 2021 CKD-EPI equation removed race. It is now the standard in many countries.
About this calculator
Formula and rules last checked 25 October 2026Written and tested by the CalculatorDex teamReport a problem
