Cockcroft–Gault CrCl Calculator
Creatinine clearance · CKD staging · Weight methods · Drug dosing guidance · KDIGO 2024 aligned
CrCl (mL/min) = [(140 − Age) × Weight (kg)] ÷ [72 × SCr (mg/dL)] × 0.85 if femaleIBW: Male = 50 + 2.3 × (Height inches − 60) · Female = 45.5 + 2.3 × (Height inches − 60)
AdjBW = IBW + 0.4 × (ABW − IBW) · Use AdjBW when ABW > 120% IBW
BMI = Weight (kg) ÷ Height (m)²
| Stage | CrCl / GFR (mL/min/1.73m²) | Description | Key actions |
|---|---|---|---|
| G1 | ≥ 90 | Normal / high | Treat comorbidities; screen for risk factors; annual monitoring |
| G2 | 60 – 89 | Mildly decreased | Estimate CKD progression; cardiovascular risk reduction |
| G3a | 45 – 59 | Mildly-moderately decreased | Monitor electrolytes, blood pressure, anaemia; dose-adjust select drugs |
| G3b | 30 – 44 | Moderately-severely decreased | Nephrology referral; bone mineral disorder management; avoid nephrotoxins |
| G4 | 15 – 29 | Severely decreased | Nephrology referral mandatory; RRT preparation; major drug dose reductions |
| G5 | < 15 (or dialysis) | Kidney failure | RRT (dialysis/transplant); maximal nephrology management; drug protocols for ESRD |
Cockcroft & Gault (1976) · KDIGO CKD Guidelines 2024 · NKF-KDOQI 2023 · SCr must be at steady state · Not validated for AKI · No data stored
- 1.Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31–41. doi:10.1159/000180580 (Original derivation — 249 adult male patients)
- 2.KDIGO 2024 CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int. 2024;105(4S):S117–S314. doi:10.1016/j.kint.2023.10.018
- 3.Kidney Disease: Improving Global Outcomes (KDIGO). KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of CKD. Kidney Int Suppl. 2013;3(1):1–150. (Foundation staging framework)
- 4.Levey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate (CKD-EPI). Ann Intern Med. 2009;150(9):604–612. (CKD-EPI vs CG for GFR estimation)
- 5.Inker LA, Eneanya ND, Coresh J, et al. New creatinine- and cystatin C-based equations to estimate GFR without race (CKD-EPI 2021). N Engl J Med. 2021;385(19):1737–1749. doi:10.1056/NEJMoa2102953
- 6.National Kidney Foundation — American Society of Nephrology Task Force. Reassessing the inclusion of race in diagnosing kidney diseases. J Am Soc Nephrol. 2021;32(6):1305–1317. (Race-free GFR equations — NKF-ASN 2021)
- 7.Pai MP. Drug dosing based on weight and body surface area: mathematical assumptions and limitations in obese adults. Pharmacotherapy. 2012;32(9):856–868. (IBW, AdjBW, ABW selection guidance)
- 8.Janmahasatian S, Duffull SB, Ash S, et al. Quantification of lean bodyweight. Clin Pharmacokinet. 2005;44(10):1051–1065. (Lean body weight in pharmacokinetics)
- 9.FDA Guidance for Industry: Pharmacokinetics in Patients with Impaired Renal Function — Study Design, Data Analysis, and Impact on Dosing and Labeling. US FDA; 2010 (updated 2024).
For educational and professional reference only. This calculator is intended to assist qualified clinicians — nephrologists, pharmacists, intensivists, and allied health professionals. It is not a substitute for clinical judgment, direct patient assessment, or institutional drug dosing protocols.
The Cockcroft–Gault equation was derived from a cohort of 249 adult male patients in 1976. It estimates creatinine clearance (CrCl) as a surrogate for GFR and is widely used for drug dosing decisions — particularly for renally cleared medications. Its accuracy is limited in: elderly patients (muscle mass overestimation), malnourished or cachectic patients, amputees, morbidly obese patients (overestimation without weight adjustment), pregnancy, and acute kidney injury (requires steady-state creatinine).
KDIGO 2024 and NKF-ASN 2021 recommend the race-free CKD-EPI 2021 equation (using creatinine ± cystatin C) as the preferred method for GFR estimation and CKD staging in clinical practice. Cockcroft-Gault remains specifically recommended by FDA guidance (2010, updated 2024) for drug dosing decisions because most clinical pharmacokinetic trials used CG-derived CrCl for dose-tier stratification.
Drug dosing guidance shown by this tool is illustrative only. Always verify dose adjustments against current product labelling, institutional formulary, and the clinical pharmacist's recommendation. This tool does not store or transmit patient data.
Last reviewed: January 2026 · KDIGO 2024 · CKD-EPI 2021 · NKF-ASN 2021 · FDA 2024 renal dosing guidance incorporated
