Carboplatin Calculator

Estimate carboplatin dose using the Calvert formula (Dose = Target AUC × (GFR + 25)), with GFR estimated from age, sex, weight, and serum creatinine via the Cockcroft-Gault equation.

Quick Facts

Calvert formula
Dose (mg) = AUC × (GFR + 25)
AUC is the target area under the curve (mg/mL·min); GFR is renal clearance in mL/min.
GFR estimate
Cockcroft-Gault CrCl
CrCl = [(140 − age) × weight(kg) × (0.85 if female)] / (72 × SCr mg/dL)
Renal function cap
GFR capped at 125 mL/min
Standard safety convention from carboplatin prescribing information, to avoid overestimating clearance and overdosing.
Typical AUC targets
4-6 (combination); 6-7 (single-agent)
The exact target is chosen by the treating oncologist based on protocol and prior therapy.

Your Results

Calculated
Estimated Creatinine Clearance
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Cockcroft-Gault CrCl estimate
GFR Used in Formula
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After optional 125 mL/min cap
Estimated Carboplatin Dose
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Calvert formula: AUC × (GFR + 25)
Dose per Body Weight
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Reference sanity-check only

Ready

Enter patient parameters and press Calculate. This tool is educational only and is not a prescribing instrument.

How the Carboplatin (Calvert Formula) Calculator Works

Carboplatin is typically dosed not by body-surface area, like many chemotherapy drugs, but by the Calvert formula, which targets a specific area under the concentration-time curve (AUC) based on the patient's renal function: Dose (mg) = Target AUC × (GFR + 25). Because GFR is rarely measured directly at the point of care, it is commonly estimated from age, sex, weight, and serum creatinine using the Cockcroft-Gault creatinine clearance equation. This calculator walks through both steps and reports the estimated creatinine clearance, the GFR actually used in the dose equation, and the resulting Calvert dose.

Step 1: Estimate creatinine clearance (Cockcroft-Gault)

CrCl (mL/min) = [(140 − age) × weight in kg × (0.85 if female, 1 if male)] / (72 × serum creatinine in mg/dL). This estimate stands in for GFR when a measured value (such as a nuclear medicine ⁵¹Cr-EDTA or iohexol clearance study) is not available. Weight entered in pounds is converted to kilograms, and creatinine entered in µmol/L is converted to mg/dL (divide by 88.4), before the equation runs.

Step 2: Apply the 125 mL/min safety cap

Because Cockcroft-Gault can overestimate true renal clearance in some patients — particularly those who are obese, edematous, or have low muscle mass — carboplatin prescribing information and common oncology practice cap the GFR used in the Calvert formula at 125 mL/min. This calculator applies that cap by default; you can switch it off to see the uncapped calculation, but the capped value is the more conservative, widely used convention.

Step 3: Calvert formula and dose per kilogram

The capped (or uncapped) GFR is added to 25 and multiplied by your target AUC to get the total dose in milligrams. The calculator also reports dose divided by body weight (mg/kg) purely as a sanity-check figure — a very high or very low mg/kg value relative to typical carboplatin ranges can flag a data-entry error before the number goes any further.

Important safety note

This tool produces an educational estimate of the Calvert-formula dose, not a prescription or medical order. Actual chemotherapy dosing must be verified by an oncology pharmacist or physician using the patient's measured or estimated GFR per institutional protocol, prior treatment history, current lab values, dose-rounding conventions, and the drug's full prescribing information. Never use this calculator, or any online tool, as the sole basis for administering carboplatin or any other chemotherapy agent.

Frequently Asked Questions

What is the Calvert formula for carboplatin dosing?
The Calvert formula calculates total carboplatin dose in milligrams as Dose = Target AUC × (GFR + 25), where AUC is the target area under the concentration-time curve in mg/mL·min and GFR is glomerular filtration rate in mL/min. It was developed to individualize carboplatin dosing by renal function instead of body-surface-area alone.
How is GFR estimated for the Calvert formula?
When measured GFR (such as a nuclear medicine clearance study) is not available, GFR is commonly estimated with the Cockcroft-Gault creatinine clearance equation: CrCl = [(140 − age) × weight in kg × (0.85 if female)] / (72 × serum creatinine in mg/dL).
Why is the estimated GFR capped at 125 mL/min?
Carboplatin prescribing information and common clinical practice cap the GFR used in the Calvert formula at 125 mL/min, because Cockcroft-Gault can overestimate renal clearance in some patients, which would otherwise inflate the calculated dose and increase toxicity risk.
What target AUC should I use for carboplatin?
Target AUC is set by the treating oncologist based on the specific protocol, typically around 4-6 mg/mL·min for combination regimens and up to 6-7 mg/mL·min for single-agent or transplant-conditioning regimens. This calculator does not choose that target for you — it only applies the Calvert formula to the value you enter.

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