GFR Calculator
Calculate estimated Glomerular Filtration Rate (eGFR) to assess kidney function. Uses CKD-EPI 2021, CKD-EPI 2009, and MDRD formulas.
Kidney Function
eGFR
91.7 mL/min
Stage 1: Normal or High
Kidney Function
eGFR
91.7 mL/min
Stage 1: Normal or High
Formula Selection
The 2021 formula is recommended by NKF and ASN. It does not use race.
Patient Information
Normal: 0.7-1.2 mg/dL (men), 0.5-1.0 mg/dL (women)
Your GFR on the CKD Scale
Formula Comparison
| Formula | eGFR (mL/min) | Stage |
|---|---|---|
| CKD-EPI 2021 | 91.7 | G1 |
| CKD-EPI 2009 | 87.4 | G2 |
| MDRD | 79.1 | G2 |
CKD Stages Reference
| Stage | GFR Range | Description |
|---|---|---|
| G1 | ≥90 | Normal or high |
| G2 | 60-89 | Mildly decreased |
| G3a | 45-59 | Mild to moderately decreased |
| G3b | 30-44 | Moderate to severely decreased |
| G4 | 15-29 | Severely decreased |
| G5 | <15 | Kidney 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.
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).
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.
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.
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).
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.
Kidney Function
eGFR
91.7 mL/min
Stage 1: Normal or High
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.