GFR Calculator: eGFR CKD-EPI 2021
This GFR calculator estimates your glomerular filtration rate, a measure of how well the kidneys filter blood, from a serum creatinine blood test. It uses the 2021 CKD-EPI creatinine equation recommended by the National Kidney Foundation and the American Society of Nephrology, which does not use race. Enter creatinine in mg/dL as shown on most US lab reports, or ยตmol/L, plus age and sex, and it returns eGFR in mL/min/1.73 m² with the matching chronic kidney disease stage from G1 to G5. It is for education and checking a lab report, not for diagnosis.
GFR Calculator
Estimate kidney filtration rate from creatinine, age and sex with the 2021 CKD-EPI equation.
How to use the GFR Calculator
- Enter your serum creatinine and pick the unit.
- Enter age and sex.
- Read the eGFR and the CKD stage.
- Discuss results with your doctor.
CKD-EPI 2021
eGFR = 142 × min(Scr/ฮบ, 1)^ฮฑ × max(Scr/ฮบ, 1)^-1.200 × 0.9938^age × 1.012 (if female), with ฮบ = 0.7 and ฮฑ = -0.241 for women, ฮบ = 0.9 and ฮฑ = -0.302 for men.
Features
- 2021 CKD-EPI race-free equation
- mg/dL or ยตmol/L creatinine
- CKD stage G1 to G5
- Explains each stage
- For adults 18 and over
- Private, runs in your browser
Frequently asked questions
What is a normal GFR?
An eGFR of 90 or higher is normal for most adults. GFR naturally declines with age.
What eGFR means kidney disease?
An eGFR below 60 for three months or more suggests chronic kidney disease. Below 15 is kidney failure.
Why does the 2021 equation not use race?
Experts removed race because it is a social, not biological, category and the old adjustment could delay care. The 2021 CKD-EPI equation is now the US standard.
How do I convert creatinine ยตmol/L to mg/dL?
Divide by 88.4. For example, 88 ยตmol/L is about 1.0 mg/dL.
Can I use this for children?
No. This equation is for adults 18 and older. Children need a pediatric formula such as the bedside Schwartz equation.