eGFR Calculator (CKD-EPI 2021)

Estimated GFR by CKD-EPI 2021 (creatinine, optionally cystatin C), Cockcroft–Gault creatinine clearance and KDIGO CKD stage — with µmol/L and mg/dL conversion.

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Calculation

Sex
Serum creatinine — Units

Leave 0 if cystatin C was not measured. With it the estimate is more accurate at atypical muscle mass.

Result

eGFR by creatinine (CKD-EPI 2021)
99 mL/min/1.73 m²

Indexed to 1.73 m² body surface area. A filtration category alone does not establish CKD.

G1–G5 filtration category
G1 — normal or high GFR (≥ 90)
eGFR by creatinine + cystatin C
enter cystatin C to calculate

The combined equation is the most accurate of the estimates

Creatinine clearance (Cockcroft–Gault)
107 mL/min

Not indexed to body surface; used in drug labels

Serum creatinine
0.96 mg/dL

CKD-EPI 2021 estimates GFR; Cockcroft–Gault estimates creatinine clearance in mL/min without body surface indexing. CKD requires evidence of chronic kidney abnormalities for at least three months; a single value cannot determine the need for dialysis. Reference ranges are population benchmarks from the cited sources. Laboratories use their own ranges, and interpretation depends on clinical context: discuss the result with your physician.

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How it is calculated

Glomerular filtration rate is the key measure of kidney function. The CKD-EPI 2021 equation (Inker et al., NEJM) derives it from serum creatinine, age and sex without the race coefficient, which has been removed from practice. When cystatin C is available the combined CKD-EPI 2021 cr-cys equation is used — more accurate in people with atypical muscle mass (athletes, sarcopenia, amputation, vegans). The calculator also shows Cockcroft–Gault creatinine clearance, still used for drug dosing, and the KDIGO CKD stage G1–G5.

Formula

eGFRcr = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.200 × 0.9938^Age × 1.012 [female] κ = 0.7 (female) / 0.9 (male); α = −0.241 (female) / −0.302 (male); Scr — creatinine, mg/dL (= µmol/L / 88.4) eGFRcr-cys = 135 × min(Scr/κ,1)^α × max(Scr/κ,1)^−0.544 × min(Scys/0.8,1)^−0.323 × max(Scys/0.8,1)^−0.778 × 0.9961^Age × 0.963 [female] Cockcroft–Gault (mL/min) = (140 − Age) × Weight (kg) × 0.85 [female] / (72 × Scr, mg/dL)

Limits of the method

CKD-EPI 2021 estimates GFR; Cockcroft–Gault estimates creatinine clearance in mL/min without body surface indexing. CKD requires evidence of chronic kidney abnormalities for at least three months; a single value cannot determine the need for dialysis.

Sources of the method

This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.

How to use the calculation

1

Enter the starting values

Glomerular filtration rate is the key measure of kidney function. The CKD-EPI 2021 equation (Inker et al., NEJM) derives it from serum creatinine, age and sex without the race coefficient, which has been removed from practice. When cystatin C is available the combined CKD-EPI 2021 cr-cys equation is used — more accurate in people with atypical muscle mass (athletes, sarcopenia, amputation, vegans). The calculator also shows Cockcroft–Gault creatinine clearance, still used for drug dosing, and the KDIGO CKD stage G1–G5.

2

Adjust the parameters

eGFRcr = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.200 × 0.9938^Age × 1.012 [female] κ = 0.7 (female) / 0.9 (male); α = −0.241 (female) / −0.302 (male); Scr — creatinine, mg/dL (= µmol/L / 88.4) eGFRcr-cys = 135 × min(Scr/κ,1)^α × max(Scr/κ,1)^−0.544 × min(Scys/0.8,1)^−0.323 × max(Scys/0.8,1)^−0.778 × 0.9961^Age × 0.963 [female] Cockcroft–Gault (mL/min) = (140 − Age) × Weight (kg) × 0.85 [female] / (72 × Scr, mg/dL)

3

Read the result

CKD-EPI 2021 estimates GFR; Cockcroft–Gault estimates creatinine clearance in mL/min without body surface indexing. CKD requires evidence of chronic kidney abnormalities for at least three months; a single value cannot determine the need for dialysis.

Frequently asked questions

What does the calculation show?

Glomerular filtration rate is the key measure of kidney function. The CKD-EPI 2021 equation (Inker et al., NEJM) derives it from serum creatinine, age and sex without the race coefficient, which has been removed from practice. When cystatin C is available the combined CKD-EPI 2021 cr-cys equation is used — more accurate in people with atypical muscle mass (athletes, sarcopenia, amputation, vegans). The calculator also shows Cockcroft–Gault creatinine clearance, still used for drug dosing, and the KDIGO CKD stage G1–G5.

What limitations apply?

CKD-EPI 2021 estimates GFR; Cockcroft–Gault estimates creatinine clearance in mL/min without body surface indexing. CKD requires evidence of chronic kidney abnormalities for at least three months; a single value cannot determine the need for dialysis.

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What next

Formula breakdowns, biomarker reference ranges and nutrition articles with cited sources are in the NutriFit knowledge base.

Go to the knowledge base