Creatinine Clearance (24-Hour Urine) Calculator
Calculate renal function using 24-hour urine collection data. Supports standard and SI units with instant staging flags.
About
Creatinine clearance (CrCl) measures the volume of blood plasma that is cleared of creatinine per unit of time. It provides a more direct measurement of Glomerular Filtration Rate (GFR) than serum-only estimates like Cockcroft-Gault, particularly when muscle mass is atypical.
This tool calculates clearance based on a strict 24-hour urine collection protocol. It flags results falling below the critical threshold of 60 mL/min, often indicating Stage 3 Chronic Kidney Disease (CKD). It supports instant switching between standard US units (mg/dL) and international SI units (µmol/L).
Formulas
The uncorrected creatinine clearance is derived from the ratio of urine creatinine to serum creatinine, adjusted for the urine flow rate.
Where:
- UCr = Urine Creatinine Concentration
- Vurine = 24-Hour Urine Volume (mL)
- PCr = Serum Creatinine
- 1440 = Minutes in 24 hours
Reference Data
| CKD Stage | Description | GFR Range (mL/min) | Action |
|---|---|---|---|
| 1 | Normal function | ≥ 90 | Observation |
| 2 | Mild loss | 60 to 89 | Estimate Progression |
| 3a | Mild to moderate | 45 to 59 | Treat Complications |
| 3b | Moderate to severe | 30 to 44 | Treat Complications |
| 4 | Severe loss | 15 to 29 | Prepare for Dialysis |
| 5 | Kidney Failure | < 15 | Dialysis / Transplant |