Calorie Calculator
Calorie Calculator
Estimate how many calories you may need each day based on your age, gender, height, weight and activity level. Use the estimate as a starting point, not a medical prescription.
Daily Calorie Calculator
Your Daily Calorie Estimate
calories/day to maintain weight
This is an estimate, not a diagnosis or a personalised medical diet plan. Actual energy needs vary.
Food Energy Converter
Convert between food Calories (kcal) and kilojoules (kJ).
Conversion Result
What Is a Calorie Calculator?
A calorie calculator estimates the energy a person may need each day. It uses details such as age, height, weight and activity level to estimate resting energy expenditure and then adjusts the estimate for activity.
How Is Daily Calorie Need Estimated?
This calculator uses the Mifflin–St Jeor equation to estimate Basal Metabolic Rate (BMR). BMR is an estimate of energy used by the body at rest. Multiplying BMR by an activity factor gives an estimated daily energy need.
Mifflin–St Jeor equation
Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
The equation uses the male or female coefficient selected in the calculator. These equations are estimates and may not fit every individual.
Activity Levels
- Sedentary: little or no planned exercise.
- Lightly active: light exercise or activity on some days.
- Moderately active: moderate exercise several days a week.
- Very active: vigorous exercise most days.
- Extra active: very demanding exercise or a physically demanding job.
Calories and Weight Management
Over time, weight change is influenced by the relationship between energy consumed and energy used. A sustained energy deficit may lead to weight loss, while an energy surplus may lead to weight gain. The rate of change varies by person.
Avoid treating a calculator result as an exact daily target. Very low calorie intake can be unsafe, and nutritional needs vary with health, medication, age, pregnancy, activity and other factors. Seek advice from a qualified healthcare professional or registered dietitian when appropriate.
Calories in Common Foods
Food energy depends on portion size and preparation. Nutrition labels and reliable food-composition databases can help estimate the energy in the foods you eat.
Calories Burned During Exercise
Energy expenditure during exercise varies with body weight, intensity, duration and fitness. Wearable devices and online estimates can be useful guides, but they are not exact measurements of calories burned.
Frequently Asked Questions
Is a calorie the same as a kilocalorie?
Food labels commonly use “Calories” to mean kilocalories (kcal). One kilocalorie equals approximately 4.184 kilojoules.
Does everyone need the same number of calories?
No. Energy needs depend on body size, age, activity and individual circumstances. This calculator provides a general estimate rather than a personalised prescription.
Can I use this calculator for children?
This calculator is designed for general adult estimates. Children and teenagers have different growth and nutritional needs and should receive age-appropriate guidance.