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Gfr Calculator

Free online gfr calculator tool. Easy to use and accurate calculations.

GFR Calculator - Kidney Function Assessment | BESTUTILS
BESTUTILS

GFR Calculator

Calculate your estimated Glomerular Filtration Rate (eGFR) using the CKD-EPI equation to assess kidney function

GFR Calculator

CKD Stages Reference

Stage 1: Normal/High
≥90 mL/min/1.73m²
Stage 2: Mild
60-89 mL/min/1.73m²
Stage 3: Moderate
30-59 mL/min/1.73m²
Stage 4: Severe
15-29 mL/min/1.73m²
Stage 5: Kidney Failure
<15 mL/min/1.73m²

What is GFR?

The Glomerular Filtration Rate (GFR) is a measure of how well your kidneys are filtering waste and excess water from your blood. It's expressed in milliliters per minute per 1.73 square meters of body surface area (mL/min/1.73m²).

GFR is the best overall indicator of kidney function and is used to diagnose and monitor chronic kidney disease (CKD). A normal GFR is typically 90 mL/min/1.73m² or higher.

This calculator uses the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation, which is considered the most accurate method for estimating GFR based on serum creatinine levels.

How to Use This Calculator

Required Information:

  • Age: Your current age in years
  • Gender: Male or Female
  • Race: Black/African American or Other
  • Serum Creatinine: Lab result in mg/dL or μmol/L

Steps to Calculate:

  1. 1 Enter your age in years
  2. 2 Select your gender
  3. 3 Choose your race category
  4. 4 Enter serum creatinine level and select units
  5. 5 Click "Calculate GFR" to get your result

Important Notes

Medical Disclaimer

This calculator is for educational purposes only and should not replace professional medical advice. Always consult with your healthcare provider for interpretation of your results and treatment decisions.

Limitations:

  • • Less accurate in certain populations (elderly, very muscular, or amputees)
  • • May not be accurate during acute kidney injury
  • • Creatinine levels can be affected by diet and muscle mass

When to Consult a Doctor:

  • • GFR below 60 mL/min/1.73m²
  • • Declining GFR over time
  • • Symptoms of kidney disease
  • • High blood pressure or diabetes