eGFR Calculator (2021 CKD-EPI)

Estimate your glomerular filtration rate (eGFR) from your creatinine, age, and sex. eGFR is the central marker of kidney function.

Updated June 25, 2026Published by Smart Medical Care SAS

Enter creatinine, age, and sex to estimate the eGFR.

The 2021 CKD-EPI Creatinine equation (race-free), recommended by international guidelines (KDIGO 2024). Valid for adults (≥ 18 years). An eGFR ≥ 60 with no other sign of kidney damage is not a disease on its own; interpretation belongs to your clinician.

Understand creatinine and eGFR

What is eGFR?

The glomerular filtration rate (GFR) measures the volume of blood your kidneys filter each minute, normalized to a standard body surface area (1.73 m²). It is estimated (eGFR) from blood creatinine, age, and sex. It is the reference marker for assessing kidney function and screening for chronic kidney disease.

The 2021 CKD-EPI equation

This calculator applies the 2021 CKD-EPI Creatinine equation, the “race-free” version (no race variable), recommended by the international KDIGO 2024 guideline.12 It replaced the older formulas (MDRD, 2009 CKD-EPI) to remove a race adjustment that has now been abandoned.

Chronic kidney disease stages (KDIGO)

eGFR sorts kidney function into stages. An eGFR ≥ 60 with no other abnormality (in particular no albuminuria) is not kidney disease.

StageeGFR (mL/min/1.73 m²)Interpretation
G1≥ 90Normal or high
G260 – 89Mildly decreased
G3a45 – 59Mildly to moderately decreased
G3b30 – 44Moderately to severely decreased
G415 – 29Severely decreased
G5< 15Kidney failure

Frequently asked questions

What is eGFR?

eGFR (estimated glomerular filtration rate) estimates the volume of blood your kidneys filter each minute, normalized to a standard body surface area (1.73 m²). It is calculated from blood creatinine, age, and sex: it is the central marker of kidney function.

Which equation is used?

This calculator uses the 2021 CKD-EPI Creatinine equation, without a race variable (race-free), recommended by the international KDIGO 2024 guideline. It replaced the older MDRD and 2009 CKD-EPI formulas.

How do I enter creatinine if it is in mg/dL?

Just select the unit on your report (mg/dL, mg/L, or µmol/L): the calculator converts automatically. In the U.S., creatinine is usually reported in mg/dL.

Does an eGFR below 90 mean kidney disease?

Not necessarily. eGFR naturally declines with age, and an eGFR ≥ 60 with no other abnormality (in particular no albuminuria) is not kidney disease. A result should be confirmed and interpreted with the other markers and your context by a clinician.

What is the difference between estimated and measured GFR?

Estimated GFR (eGFR) is calculated from creatinine; it is fast and sufficient for routine care. Measured GFR (with a tracer) is more precise but reserved for special situations. Both target the same quantity: the kidneys’ filtering capacity.

Is the calculation valid for children or during pregnancy?

No. The 2021 CKD-EPI equation is validated in adults (≥ 18 years). In children, specific pediatric formulas are used; during pregnancy, eGFR is unreliable and requires dedicated medical follow-up.

Does this result replace a doctor’s advice?

No. The calculator provides an estimate for information only. Diagnosing and monitoring kidney disease rests on the full workup (creatinine, albuminuria, imaging…) and belongs to your clinician.

To switch between creatinine units, see our unit converter.

Disclaimer. This tool provides an estimate for information only, valid in adults. It does not diagnose anything and does not replace the advice of a healthcare professional. Interpreting an eGFR depends on your full workup and your situation.

Sources

  1. 1

    Inker LA, et al. — “New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race.” N Engl J Med, 2021. · PubMed · DOI

  2. 2

    KDIGO — “KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease.” Kidney Int, 2024. · PubMed · DOI