Calculators

Free calculators

Work out your numbers in seconds: BMI, daily energy, protein and macros, in kilograms or pounds and with kilojoules as well as calories. Nothing you type is saved or sent.

Updated 21 October 2026. Sources named on the page.

No sign-in, no download, works on your phone
Every formula shown with a worked example and its source
For adults aged 19 and over; estimates, not medical advice
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Every claim names its sourceNothing you type is savedFree, no sign upFor adults aged 19 and overPrivate by default

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All calculators

BMI calculatorWeight and height to BMI and the usual adult range.TDEE calculatorDaily energy in kcal and kJ from age, sex, height, weight and activity.Protein calculatorThe national reference amount for your age, sex and weight.Macro calculatorCalories to grams of protein, carbs and fat.Calorie calculatorDaily calories to keep, lose or gain weight, with safe limits.Calorie deficit calculatorA gentle deficit with a safe floor.kJ to calories converterKilojoules to kilocalories and back.Water intake calculatorA guideline amount of fluid a day.Sleep cycle calculatorBedtimes and wake times from sleep cycles.Habit streak plannerHow long until a habit has run 66 days.

Questions

Are these calculators free?

Yes. They need no sign-in and nothing you type is saved or sent.

Are the results medical advice?

No. They are estimates for healthy adults aged 19 and over. Talk to a doctor or an accredited practising dietitian about your own health.

Can I use pounds, feet and inches?

Yes. Each calculator that uses height or weight has a metric and imperial switch, and energy is shown in both kilojoules and kilocalories.

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