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  1. Home
  2. Health & Fitness
  3. GFR Calculator

GFR Calculator

Calculate estimated Glomerular Filtration Rate (eGFR) to assess kidney function. Uses CKD-EPI 2021, CKD-EPI 2009, and MDRD formulas.

Formula:eGFR = 142 × min(Scr/κ,1)^α × max(Scr/κ,1)^-1.200

Kidney Function

eGFR

91.7 mL/min

Stage 1: Normal or High

Normal kidney function. Continue monitoring if risk factors present.
CKD StageG1
Formula UsedCKD-EPI 2021

Kidney Function

eGFR

91.7 mL/min

Stage 1: Normal or High

Normal kidney function. Continue monitoring if risk factors present.
CKD StageG1
Formula UsedCKD-EPI 2021

Formula Selection

The 2021 formula is recommended by NKF and ASN. It does not use race.

Patient Information

mg/dL

Normal: 0.7-1.2 mg/dL (men), 0.5-1.0 mg/dL (women)

years

Your GFR on the CKD Scale

91.7
120+90604530150

Formula Comparison

FormulaeGFR (mL/min)Stage
CKD-EPI 202191.7G1
CKD-EPI 200987.4G2
MDRD79.1G2

CKD Stages Reference

StageGFR RangeDescription
G1≥90Normal or high
G260-89Mildly decreased
G3a45-59Mild to moderately decreased
G3b30-44Moderate to severely decreased
G415-29Severely decreased
G5<15Kidney failure

Normal Creatinine Levels

Adult Males

0.7-1.2 mg/dL

Adult Females

0.5-1.0 mg/dL

Note: Creatinine levels can be affected by muscle mass, diet, medications, and hydration status.

Kidney Health Scenarios

Explore how changes affect your results

Your GFR vs Population

Compared to the general population

Your eGFR

91.7 mL/min

Percentile

53th

Above average - great job!

Distribution

You

Low

50.0

Below Average

70.0

Average

90.0

Above Average

105.0

Excellent

120.0

Your Ranking

Top 47%

47% are lower

Kidney Health Tips

Based on your results

0/4 completed
⚕️ MedicalOptional

Your GFR Status

Your GFR of 91.7 mL/min indicates normal or high kidney function. Focus on maintaining this through healthy lifestyle choices.

⚕️ MedicalImportant

Blood Pressure Control

Keep blood pressure below 130/80 mmHg. High blood pressure is a leading cause of kidney damage.

🌙 LifestyleRecommended

Stay Hydrated

Drink adequate water daily. Proper hydration helps kidneys filter waste efficiently.

Quick Answer

GFR (Glomerular Filtration Rate) measures kidney function. Normal GFR: 90+ mL/min/1.73m². eGFR calculated from creatinine, age, sex. CKD stages: G1 (90+), G2 (60-89), G3 (30-59), G4 (15-29), G5 (<15).

Key Facts

  • Normal GFR: 90+ mL/min/1.73m²
  • Calculated from serum creatinine
  • CKD-EPI formula most accurate
  • Declines with age (~1 mL/min per year after 40)
  • Race-neutral formulas now standard
  • GFR classifies kidney disease stages

Frequently Asked Questions

GFR measures how well your kidneys filter waste from blood, expressed in mL/min/1.73m². Normal GFR is 90-120. It's the best measure of kidney function and is used to stage chronic kidney disease (CKD).

Rate at which kidneys filter blood. Normal: 90-120 mL/min. Best measure of kidney function.

Stage 1: Normal (GFR ≥90). Stage 2: Mild loss (60-89). Stage 3a: Mild-moderate (45-59). Stage 3b: Moderate-severe (30-44). Stage 4: Severe (15-29). Stage 5: Kidney failure (<15). Lower stages require more intensive treatment.

Stage 1-2: Mild. Stage 3: Moderate. Stage 4: Severe. Stage 5: Kidney failure.

The 2021 formula removes race from the calculation. Previous formulas used race coefficients that could lead to delayed diagnosis and treatment for Black patients. The new formula provides more equitable care across all populations.

Removes race for more equitable diagnosis. Previous formulas could delay treatment for Black patients.

Creatinine is a waste product from muscle metabolism. Healthy kidneys filter it out of blood into urine. High blood creatinine suggests kidneys aren't filtering well. Normal levels: 0.7-1.2 mg/dL (men), 0.5-1.0 mg/dL (women).

Muscle waste product filtered by kidneys. High levels indicate poor kidney function.

Manage blood pressure (<130/80), control blood sugar if diabetic, reduce salt intake, stay hydrated, exercise regularly, avoid NSAIDs, quit smoking, and limit alcohol. Some GFR loss with age is normal but can be slowed.

Control BP and blood sugar, reduce salt, stay hydrated, avoid NSAIDs, exercise regularly.

Kidney Function

eGFR

91.7 mL/min

Stage 1: Normal or High

Normal kidney function. Continue monitoring if risk factors present.
CKD StageG1
Formula UsedCKD-EPI 2021

Medical Disclaimer

This calculator is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider before making any health-related decisions.