Creatinine clearance (Cockcroft-Gault)
The CrCl estimate many product labels refer to for dose adjustment
- EHRA 2021 NOAC guide (dosing)
Sources last checked: 2026-10-13
Creatinine clearance (Cockcroft-Gault)
The CrCl estimate many product labels refer to for dose adjustment
Calculates with the actual body weight entered. In obesity, many dosing sources specify ideal or adjusted weight; the product information states which weight applies.
What is the Creatinine clearance (Cockcroft-Gault)?
The Cockcroft-Gault equation estimates creatinine clearance (CrCl, mL/min) from age, body weight, serum creatinine and sex. Cockcroft and Gault derived it in 1976 from 249 men in Canada, with a 15 % reduction suggested for women. It is not indexed to body surface area and remains the basis of many drug-dosing recommendations, including those for DOACs.
When to use it
- Dosing renally cleared drugs whose label specifies creatinine clearance — notably dabigatran, rivaroxaban, apixaban and edoxaban (EHRA practical guide).
- Dosing narrow-therapeutic-range drugs (aminoglycosides, vancomycin, some chemotherapy) when the local protocol uses CrCl.
- Checking eligibility thresholds in trials and product information that were defined with Cockcroft-Gault.
When not to use it
- Staging chronic kidney disease — use an eGFR equation (CKD-EPI or EKFC) and KDIGO categories.
- Unstable kidney function (acute kidney injury, dialysis).
- Marked obesity or oedema with actual body weight, unless the drug reference specifies it — weight choice changes the result substantially.
How it is calculated
CrCl (mL/min) = (140 − age) × weight (kg) / (72 × SCr in mg/dL) × 0.85 [if female] With SCr in µmol/L: CrCl ≈ (140 − age) × weight × 1.23 / SCr (× 0.85 if female)
Clinical pearls and limitations
- Calculates with the actual body weight entered. In obesity, many dosing sources specify ideal or adjusted weight; the product information states which weight applies.
- Creatinine in µmol/L: divide by 88.4 for mg/dL, or use CrCl ≈ (140 − age) × weight × 1.23 / SCr(µmol/L), × 0.85 for women.
- Modern IDMS-standardised creatinine assays read lower than the methods of 1976, so Cockcroft-Gault tends to overestimate clearance slightly.
- In older, frail patients with low muscle mass, a 'normal' creatinine can hide a CrCl below 30 mL/min — relevant for DOACs and other renally cleared drugs.
- Which weight (actual, ideal, adjusted) applies is drug-specific and stated in the product information or local guidance.
Frequently asked questions
Cockcroft-Gault or eGFR for DOAC dosing?
The pivotal DOAC trials used Cockcroft-Gault creatinine clearance, and the EHRA 2021 practical guide recommends Cockcroft-Gault for DOAC dosing because eGFR equations can overestimate kidney function in older and low-weight patients.
Which weight should I use in Cockcroft-Gault?
The original equation used actual body weight. In obesity, many references use ideal or adjusted body weight; the right choice depends on the drug and local protocol. This calculator uses the weight you enter.
Why is Cockcroft-Gault not indexed to 1.73 m²?
It estimates the patient's absolute creatinine clearance in mL/min, which is what determines drug elimination. eGFR equations report a value normalised to 1.73 m² body surface area for staging.
Evidence and guidelines
- Primary source: Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 1976;16(1):31-41.
- Steffel J et al. 2021 European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation. Europace 2021;23(10):1612-1676 (kidney function for NOAC dosing assessed with Cockcroft-Gault).
- KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int 2024;105(4S):S117-S314 (section 4.2, drug dosing and the limitations of Cockcroft-Gault).
Have a follow-up question?
Medelix answers clinical questions from current guidelines and studies — every statement with its source.
Ask Medelix about the Creatinine clearance (Cockcroft-Gault)Related calculators
Embed this calculatorFree to use on your website, intranet or teaching page. Copy the code below.
<iframe src="https://medelix.ai/en/embed/cockcroft-gault" title="Creatinine clearance (Cockcroft-Gault) – Medelix" width="100%" height="620" style="border:0;max-width:720px" loading="lazy"></iframe>
<p><a href="https://medelix.ai/en/calculators/creatinine-clearance-cockcroft-gault">Creatinine clearance (Cockcroft-Gault) calculator by Medelix</a></p>For healthcare professionals and medical students. These tools support, and do not replace, clinical judgement. Always check results against the original source and your local protocols.