Body mass index
BMI = weight (kg) ÷ height (m)²
Categories follow the standard adult WHO cut-offs.
Body metrics
BMI, body surface area and weight descriptors
Sex (for weight formulas)(select one)Required — ideal, adjusted and lean body weight differ by sex.
Calculated result
Enter height, weight and sex to calculate.
Renal function
Cockcroft–Gault clearance and CKD-EPI 2021 eGFR
Creatinine unit(select one)Australian laboratories usually report µmol/L.
Sex(select one)Required — Cockcroft–Gault and CKD-EPI both use sex.
Calculated result
Enter age, weight, creatinine, unit and sex to calculate.
Infusion rate
Pump rate from your ordered dose — no medicine database, you supply the numbers
Dose interval
Weight based
Calculated result
Enter the ordered dose and bag details to calculate.
Drip rate & fluids
Gravity drip rate, infusion duration and 4-2-1 maintenance estimate
Drop factor (gtt/mL)
Calculated result
Enter a volume and rate, or a weight, to calculate.
Formulas and clinical reference
Body surface area
Mosteller = √(height (cm) × weight (kg) ÷ 3600)
Du Bois is shown alongside for comparison.
Ideal / adjusted body weight
IBW = base + 2.3 × (height in inches − 60); ABW = IBW + 0.4 × (actual − IBW)
Base is 50 kg (male) or 45.5 kg (female). Lean body weight uses the Boer equation.
Creatinine clearance
CrCl = ((140 − age) × weight) ÷ (72 × SCr mg/dL), × 0.85 if female
Cockcroft–Gault. Choose the body weight descriptor appropriate to your local protocol.
eGFR
CKD-EPI 2021 creatinine equation (race-free), mL/min/1.73 m²
Staging labels follow KDIGO G1–G5 categories.
Infusion rate
Rate (mL/h) = amount required per hour ÷ concentration (amount per mL)
You supply the dose; this tool stores no product- or medicine-specific dosing data.
Gravity drip rate
drops/min = rate (mL/h) × drop factor (gtt/mL) ÷ 60
Common drop factors: 10, 15, 20 (macro) and 60 gtt/mL (micro).
Maintenance fluids
Holliday–Segar 4-2-1: 4 mL/kg/h (first 10 kg) + 2 (next 10 kg) + 1 (remainder)
An estimate only; adjust for clinical status, losses and local policy.
Decision support for healthcare professionals only. Verify every result against your local protocol before clinical use. This tool contains no medicine-specific dose data on this page and no patient records.