GFR Calculator

    Estimate kidney function (glomerular filtration rate) using the CKD-EPI equation with CKD staging.

    GFR Calculator

    Enter your serum creatinine level from a blood test. Normal range: 0.6-1.2 mg/dL

    About GFR & Kidney Function

    Glomerular Filtration Rate (GFR) is the best overall measure of kidney function. It tells how well your kidneys are filtering waste from your blood. GFR is calculated using the CKD-EPI equation, which considers your age, gender, race, and serum creatinine level.

    •CKD Stages by GFR

    • –Stage 1 (GFR ≥90): Normal kidney function with other signs of kidney damage
    • –Stage 2 (GFR 60-89): Mild reduction in kidney function
    • –Stage 3a (GFR 45-59): Mild to moderate reduction
    • –Stage 3b (GFR 30-44): Moderate to severe reduction
    • –Stage 4 (GFR 15-29): Severe reduction in kidney function
    • –Stage 5 (GFR <15): Kidney failure (ESRD - End-Stage Renal Disease)

    •The CKD-EPI Equation

    • –Most Accurate: 2021 CKD-EPI equation without race coefficient
    • –Factors Considered: Age, gender, race, and serum creatinine
    • –Standardized: Results normalized to body surface area (1.73m²)
    • –Clinical Standard: Recommended by KDIGO guidelines

    •Protecting Your Kidneys

    • –Control Blood Pressure: Keep BP below 130/80 mmHg
    • –Manage Diabetes: Maintain HbA1c below 7% if diabetic
    • –Healthy Diet: Limit sodium, protein, and phosphorus as advised
    • –Stay Hydrated: Drink adequate water unless fluid-restricted
    • –Avoid NSAIDs: Limit ibuprofen and similar medications

    •When to See a Nephrologist

    • –GFR <60: CKD Stage 3 or higher requires specialist care
    • –Rapid Decline: GFR dropping > 5 mL/min/year
    • –Protein in Urine: Persistent albuminuria or proteinuria
    • –Symptoms: Swelling, fatigue, changes in urination

    Related Tools