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Daily calorie calculator
Find out how many calories your body needs to keep your weight, lose gently or gain. The calculator uses age, height, weight and activity and suggests a balance of protein, fat and carbs.
A calculation you can check
This estimate is for adults aged 18 or older. The Mifflin–St Jeor equation uses weight in kilograms, height in centimetres and age: 10 × weight + 6.25 × height − 5 × age. It then adds 5 for the male branch or subtracts 161 for the female branch. This estimates resting expenditure; it does not measure your metabolism.
An activity factor from 1.2 to 1.9 turns that estimate into an approximate daily expenditure. The category is subjective: three short walks and three demanding workouts are different patterns. The result shows your selected inputs and intermediate calculations so you can check the arithmetic.
What goals and macros mean
The loss setting reduces the estimate by 15%; the gain setting increases it by 10%. These are model settings, not evidence that the resulting intake is safe or suitable for you. A numerical floor also cannot establish an individual minimum requirement. The example protein, fat and carbohydrate split is calculated from the same estimate and is not a prescribed diet.
When this tool does not apply
Do not use it for children, pregnancy or breastfeeding. Medical restrictions, recovery from illness and treatment need individual assessment. If thoughts about food or weight cause distress, discussing how you feel with a professional may be more useful than trying to match a number.
A useful next step
Write down what activity looked like during an ordinary week and which assumptions you selected. Compare the estimate with your routine and questions you want to ask a professional. Recipe ingredients and portions can help with meal planning; the calculator does not promise a rate of weight change.
NIDDK: adult weight planning and its limits
This calculator is for information only and does not replace medical advice.