Every calculator we’ve built, in one place.
Every calculator here is built from a named, published source and tested before it goes live. A few more are still in development. See how we build them.
Nutrition
Protein Intake Calculator
Get a personalized daily protein range based on your weight, activity level, and goal — updates instantly as you type.
Open calculatorMacro Split Calculator
Turn a calorie target into protein, carb, and fat grams for your chosen diet style.
In developmentWeight management & body composition
Calorie Needs (TDEE) Calculator
Estimate your daily calorie needs for maintenance, gradual loss, or gradual gain, using the Mifflin-St Jeor equation.
Open calculator Body composition · LiveIdeal Body Weight and BMI Calculator
BMI with WHO or Asian cut-offs, plus ideal body weight from four formulas and an adjusted body weight for dosing.
Open calculator Vitals · LiveBody Fat Percentage Estimator
A U.S. Navy circumference-method estimate of body fat percentage from a few tape measurements.
Open calculatorPaediatrics & growth
Height Velocity Calculator
Work out a child’s growth rate in cm per year from two measurements, with context by pubertal stage.
Open calculator Paediatrics · LivePaediatric Dose Calculator
Weight-based dose arithmetic with maximum-dose caps and liquid volume, using a reference dose you supply.
Open calculator Paediatrics · LiveIbuprofen Dose Calculator
Weight-based ibuprofen dose for children in mg and mL, with dosing interval and the 24-hour maximum.
Open calculator Paediatrics · LiveCefalexin Dose Calculator
BNFc/NICE weight-based cefalexin dosing for children, with frequency and suspension volume.
Open calculatorMedication tools
Steroid Conversion Calculator
Convert between prednisolone, hydrocortisone, dexamethasone and other corticosteroids using BNF equivalent doses.
Open calculator Medicines · LiveMedication Tapering Calculator
Lay out a step-down schedule with fixed or percentage reductions, dose rounding and calendar dates.
Open calculator Medicines · LiveMTX Dose Calculator
BSA-based weekly methotrexate dose for paediatric use, with tablet count and once-weekly safety checks.
Open calculator Medicines · LiveIron Deficit Calculator
Estimate total iron deficit with the Ganzoni formula from weight and haemoglobin.
Open calculatorClinical scores & lab conversions
RMI Calculator
Risk of Malignancy Index (RMI I) from CA-125, ultrasound features and menopausal status, with the NICE threshold.
Open calculator Diabetes · LiveGlucose to HbA1c Calculator
Convert average glucose to estimated HbA1c and back, in mg/dL, mmol/L, % and mmol/mol.
Open calculatorFitness
Heart Rate Zone Calculator
Find your training zones for fat-burning, cardio, and peak-effort work.
In developmentHydration
Water Intake Calculator
A daily fluid-intake estimate adjusted for body weight, climate, and activity.
In development