Renal & Electrolytes

Creatinine Clearance (Cockcroft-Gault) Calculator

Cockcroft–Gault creatinine clearance from age, weight, creatinine and sex; the estimate most drug labels use for renal dosing.

Reviewed by Alex G, BSN, RN, CEN, CCRN, CMC, NREMT-P · From the Reference tab of the app

Turn on JavaScript to use this calculator, or open it in the web app.

Formula

CrCl = [(140 - age) × weight(kg)] / (72 × SCr) × [0.85 if Female]

How it is used

• Still heavily used by pharmacists to dose antibiotics and other renally cleared medications in the ICU.

Same formula as the app. Open it in the web app.

Related one-pagers

• CRRT (Continuous Renal Replacement)Diffusion moves solute down a concentration gradient into countercurrent dialysate. At CRRT flows (dialysate 1–2 L/h against blood 9–15 L/h) the dialysate leaves nearly saturated, so clearance of urea (60 Da), creatinine and potassium roughly equals the dialysate rate, while middle molecules (β₂-microglobulin, myoglobin, cytokines) barely diffuse. Convection drags solute across with plasma water pushed by TMP; replacement fluid returns the volume. Adsorption is a small third route (AN69ST, oXiris).
• Acute Kidney InjurySteady-state equations (Cockcroft-Gault, CKD-EPI) overestimate GFR while creatinine climbs and underestimate it in recovery; the 2026 draft says to dose from creatinine and urine trends and to consider kinetic eGFR (2B). Loading doses stay full because resuscitation expands distribution, and admission AKI resolved within 48 h in 57.2% of infected patients (Crass 2019), so many pharmacists delay cutting wide-margin antibiotics.
• Electrolyte Imbalances
• ABG Interpretation in 6 Steps

Related calculators

• Anion Gap
• BUN/Cr Ratio
• Corrected Calcium
• Corrected Sodium (Hyperglycemia)
• CRRT Effluent Dose (mL/kg/h)
• Fractional Excretion of Sodium (FENa)
• Fractional Excretion of Urea (FEUrea)
• Free Water Deficit

For education and exam preparation only. Follow your institution’s protocols. For education and exam preparation only. Verify results independently and follow your institution’s protocols. Not a substitute for clinical judgment.