Online Medical Calculators

Free dosage, calorie, weight & lab calculators — instant results, no signup

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Anthropometry

6 calculators

Body measurements, composition, and energy requirement tools.

Basal Metabolic Rate (BMR) — Mifflin-St Jeor equation
Body Fat Percentage — US Navy circumference method
Body Mass Index (BMI) — BMI = kg / m²

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Fitness & Hydration

2 calculators

Daily hydration and heart-rate zone planning calculators.

Daily Water Intake — 35 ml/kg/day
Target Heart Rate Zones — Karvonen method

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Clinical

4 calculators

Common bedside and lab-derived medical calculation tools.

Anion Gap — AG = Na - (Cl + HCO3)
Corrected Calcium — Corrected Ca = measured + 0.8 × (4 - albumin)
Creatinine Clearance (CrCl) — Cockcroft-Gault equation

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A quick look at 12 of 12 tools. Open any card for instant results.

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Basal Metabolic Rate (BMR)

Estimated resting daily energy expenditure.

Mifflin-St Jeor equation

Body Fat Percentage

Body-fat estimate from circumference measurements.

US Navy circumference method

Body Mass Index (BMI)

Screening index for weight status using height and weight.

BMI = kg / m²

Body Surface Area (BSA)

Surface area estimate frequently used in dosing workflows.

Mosteller equation

Ideal Body Weight

Reference weight estimate based on height and sex.

Devine equation

Total Daily Energy Expenditure (TDEE)

Estimated daily calories including activity.

TDEE = BMR × activity factor

Anion Gap

Calculated serum anion gap from routine electrolytes.

AG = Na - (Cl + HCO3)

Corrected Calcium

Albumin-corrected total calcium estimate.

Corrected Ca = measured + 0.8 × (4 - albumin)

Creatinine Clearance (CrCl)

Estimated creatinine clearance from age, sex, weight, and creatinine.

Cockcroft-Gault equation

Mean Arterial Pressure (MAP)

Perfusion pressure estimate from blood pressure values.

MAP = (SBP + 2 × DBP) / 3

Daily Water Intake

Hydration target based on body weight.

35 ml/kg/day

Target Heart Rate Zones

Training zones using age and resting heart rate.

Karvonen method