The Creatinine Clearance (Cockcroft-Gault Equation) calculator estimates kidney function through the creatinine clearance rate, reflecting how effectively the kidneys filter waste. This tool requires input on age, gender, weight, height, and serum creatinine level.

Key parameters:
- Age (years): 18 to 120
- Gender: Male or Female
- Weight: in kilograms (20–200 kg) or pounds (44–440 lbs)
- Height: in centimeters (120–220 cm) or inches (48–87 in)
- Creatinine: in mg/dL (0.1–20) or µmol/L (8.84–1768.4)

The process involves:

1. **Unit Conversion**:
   - Convert weight from pounds to kilograms, if necessary, using 1 kg = 2.20462 lbs.
   - Convert height from centimeters to inches, if necessary, using 1 inch = 2.54 cm.
   - Convert creatinine from µmol/L to mg/dL, if necessary, using 1 mg/dL = 88.4 µmol/L.

2. **Ideal Body Weight (IBW) Calculation**:
   - For males: IBW = 50 + 2.3 * (height in inches - 60)
   - For females: IBW = 45.5 + 2.3 * (height in inches - 60)

3. **Adjusted Body Weight (ABW) Calculation**:
   - ABW = IBW + 0.4 * (actual weight - IBW)

4. **Creatinine Clearance Calculation**:
   - Original CrCl (using actual weight): ((140 - age) * weight) / (72 * creatinine)
   - IBW CrCl (using ideal weight): ((140 - age) * IBW) / (72 * creatinine)
   - ABW CrCl (using adjusted weight): ((140 - age) * ABW) / (72 * creatinine)

5. **Gender Adjustment**:
   - For females, each calculated CrCl value needs multiplying by 0.85.

Final outputs include:
- Original CrCl, reflecting estimation with actual weight.
- IBW CrCl, using ideal weight.
- ABW CrCl, calculated with adjusted weight.
- Weight used for the computation, displayed in kilograms.

These outputs, rendered in mL/min and rounded to one decimal place, facilitate the assessment of kidney function and inform clinical decisions regarding medication dosing. Better kidney filtration capabilities correspond to higher clearance scores, guiding clinicians in interpreting renal health.

The Cockcroft-Gault equation calculates creatinine clearance to estimate kidney function and guide medication dosing. It considers age, weight, gender, and serum creatinine, incorporating adjustments for body weight when necessary. This widely-used formula helps healthcare providers assess renal function and adjust medication doses accordingly.