GFR Calculator (Kidney Function)
Calculate eGFR for CKD staging and renal function assessment (CKD-EPI & MDRD)
Glomerular Filtration Rate (GFR)
eGFR estimates kidney filtration capacity (ml/min/1.73m²). Critical for CKD staging, drug dosing (antibiotics, chemotherapy), contrast safety. Uses CKD-EPI (most accurate) and MDRD formulas with age, gender, creatinine, and race adjustments.
Clinical GFR Formulas
- Enter serum creatinine, age, gender, and ethnicity.
- CKD-EPI (new standard) vs MDRD (traditional).
- Get CKD stage + medication safety guidelines.
FAQs
- CKD-EPI vs MDRD accuracy?
- CKD-EPI ±5% vs MDRD ±8%. CKD-EPI better for GFR >60 and non-Black patients.
- Why creatinine-based only?
- Creatinine most standardized. Cystatin C (±3%) alternative but 3x costlier.
- Fasting affect creatinine?
- No – creatinine stable. Muscle mass dominant factor (bodybuilders 1.5-2.0 mg/dL normal).
- Black adjustment controversy?
- CKD-EPI 2021 removed race (more equitable). MDRD retains for clinical validation.
- When to worry about GFR drop?
- >25% acute drop = AKI. >5 ml/min/yr chronic decline = progression.