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eGFR (CKD-EPI 2021)

Provide age, sex, and serum creatinine to estimate eGFR (mL/min/1.73 m²). This equation omits race and aligns with current KDIGO recommendations.

Provide age, sex, and creatinine to estimate eGFR.

How to Use This Calculator

1

Use stable serum creatinine values

The CKD-EPI equation assumes steady-state creatinine. Avoid use in acute kidney injury or rapidly changing renal function.

2

Select correct units

Switch between mg/dL and µmol/L depending on lab reporting. The calculator converts automatically.

3

Interpret alongside albuminuria

Combine eGFR with albumin-creatinine ratio to stage CKD and plan monitoring, nephrology referral, and renoprotective therapy.

Formula

eGFR = 142 × min(Scr/κ, 1)α × max(Scr/κ, 1)−1.200 × 0.9938Age × 1.012 (if female)

Where κ = 0.7 (female) or 0.9 (male); α = −0.241 (female) or −0.302 (male); Scr in mg/dL.

Full Description

The CKD-EPI 2021 creatinine equation estimates glomerular filtration rate without using race. It is now recommended by KDIGO and the National Kidney Foundation. Use eGFR to stage chronic kidney disease, guide medication dosing, and assess cardiovascular risk. Combine with markers of kidney damage (e.g., albuminuria, imaging) to confirm CKD and plan follow-up intervals.

Frequently Asked Questions

How does this differ from MDRD?

CKD-EPI is more accurate at higher GFR levels and is now the preferred method in adults. MDRD often underestimates GFR when kidney function is near normal.

Do I need height or weight?

No. The equation normalises to 1.73 m² body surface area. For drug dosing, consider Cockcroft–Gault or adjust for actual body surface area when necessary.

Can I use this in pregnancy or extremes of muscle mass?

Creatinine-based eGFR is less accurate in pregnancy, cachexia, amputation, or severe obesity. Consider cystatin C–based equations or measured GFR in these scenarios.

What about paediatric patients?

The CKD-EPI equation is validated for adults ≥18 years. Use the Schwartz formula for children.