Calcmedical

eGFR Calculator (CKD-EPI 2021)

NephrologyGeneral Medicine

Medical context

Estimate glomerular filtration rate with the race-free CKD-EPI 2021 creatinine equation and view CKD stage banding.

Nephrology and medicine teams use this when interpreting renal function, electrolytes, or fluid plans.

This page explains the eGFR formula, how to interpret the output, known limitations, and peer-reviewed references so you can verify results against primary sources and local protocols.

It is grouped under Nephrology because kidney function, electrolytes, and renal dosing helpers.

How to use this calculator

  1. Enter the values requested by the eGFR calculator using the units shown beside each field.
  2. Review the calculated result and read the interpretation section before acting on the output.
  3. Check limitations and references if the result will change management, dosing, or disposition.
  4. Use the related calculators section when you need supporting values (for example electrolytes, weight, or complementary risk scores).

Calculator

Result

67 mL/min/1.73 m²

G2 (mildly decreased)

CKD-EPI 2021 creatinine equation (race-free).

Educational use only. Confirm results with clinical judgment, primary sources, and local protocols. Not a substitute for professional medical advice. Full disclaimer.

Formula

eGFR = 142 × min(Scr/κ,1)^α × max(Scr/κ,1)^−1.200 × 0.9938^Age × (1.012 if female), where κ/α differ by sex.

Interpretation

Map eGFR to KDIGO G stages (G1–G5). Staging also depends on albuminuria and clinical context.

Limitations

Less accurate at extremes of muscle mass, amputation, pregnancy, and rapidly changing creatinine. Confirm with measured GFR when decisions are high-stakes.

Frequently asked questions

Is this the race-free eGFR equation?
Yes. This tool uses CKD-EPI 2021 creatinine, which does not include a race coefficient.
What units does creatinine use?
Enter serum creatinine in mg/dL. Convert µmol/L by dividing by 88.4.
Is the eGFR result enough to make a treatment decision?
No. Calculators support medical decision-making but do not replace examination, shared decision-making, institutional protocols, or consultant input when stakes are high.

References