Kidney GFR Calculator

Estimate glomerular filtration rate (eGFR) from creatinine. See CKD stage classification.

By Konstantin Iakovlev · Updated April 2026 · Source: CDC

mg/dL
Sex

Estimated GFR

94.6

mL/min/1.73m²

Stage G1: Normal or High

CKD Stages

G1 — Normal or High≥ 90
G2 — Mildly Decreased60–89
G3a — Mild-Moderate Decrease45–59
G3b — Moderate-Severe Decrease30–44
G4 — Severely Decreased15–29
G5 — Kidney Failure< 15

Uses the CKD-EPI 2021 race-free equation. This is an estimate — actual kidney function may differ. Factors like muscle mass, diet, and hydration can affect creatinine levels.

Use the Kidney GFR Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

Blood creatinine levels feed an estimate of your Glomerular Filtration Rate (eGFR), one of the most informative markers of how well your kidneys are working. Tracking that number helps catch and follow Chronic Kidney Disease (CKD) in its earliest, most treatable stages. Under 2026 health guidelines, an eGFR holding below 60 mL/min/1.73m² for three months or longer points to CKD.

At the core of the estimate is the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation, regarded as the most accurate way to gauge GFR in adults. It folds together your creatinine level, age, sex, and race to produce an eGFR tailored to you. Reliable as the equation is, the output stays an estimate rather than a direct measurement of filtration.

Diagnosis and treatment of any kidney condition belong with a healthcare professional, so resist the urge to interpret a result on your own, since muscle mass, diet, and various medications can all sway creatinine. One reading is only a moment in time; the trend across repeated measurements tells you far more about kidney health than any single value.

Example: Understanding Your eGFR Result

  1. 1 A 55-year-old female, non-African American, has a serum creatinine of 1.2 mg/dL.
  2. 2 Using the CKD-EPI 2021 formula, the calculator would input these values: Creatinine = 1.2 mg/dL, Age = 55, Sex = Female, Race = Non-African American. The formula calculates an eGFR based on these parameters.
  3. 3 The calculated eGFR is approximately 52 mL/min/1.73m².
  4. 4 An eGFR of 52 mL/min/1.73m² indicates Stage 3A Chronic Kidney Disease (CKD). This means there is a mild to moderate decrease in kidney function. Further consultation with a doctor is recommended to discuss lifestyle changes, monitoring, and potential treatment options.

Source: CDC · Last updated: April 2026

Frequently Asked Questions

What is a normal GFR level?
A normal GFR is 90 mL/min or higher. GFR of 60-89 indicates mildly decreased kidney function (CKD stage 2). Below 60 for three months or more indicates chronic kidney disease. Below 15 is kidney failure (stage 5) potentially requiring dialysis.
How is GFR calculated?
eGFR is estimated from serum creatinine levels using the CKD-EPI equation, factoring in age and sex. The 2021 CKD-EPI equation removed the race variable. A blood test for creatinine is the primary input, and your doctor calculates eGFR automatically.
Can I improve my GFR?
Mildly reduced GFR can sometimes improve with lifestyle changes: staying hydrated, reducing sodium, controlling blood pressure and blood sugar, avoiding NSAIDs, and maintaining a healthy weight. Significant kidney damage is generally not reversible, but progression can be slowed.

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