How many calories should you eat each day? The answer depends on your age, sex, size and how active you are. This calculator estimates your daily needs and shows target calories for maintaining, losing or gaining weight.
How the calorie calculator works
It first estimates your basal metabolic rate (BMR), the energy your body burns at complete rest to keep you breathing, circulating blood and maintaining body temperature. It uses the Mifflin-St Jeor equation, which research has found to be among the most accurate for healthy adults:
- Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
- Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
Your BMR is then multiplied by an activity factor to estimate your total daily energy expenditure (TDEE), the calories you burn in a typical day including movement and exercise.
| Activity level | Multiplier |
|---|---|
| Sedentary (little or no exercise) | × 1.2 |
| Lightly active (1 to 3 days a week) | × 1.375 |
| Moderately active (3 to 5 days a week) | × 1.55 |
| Very active (6 to 7 days a week) | × 1.725 |
| Extra active (physical job plus training) | × 1.9 |
Because the activity factor already includes your exercise, do not add exercise calories on top. Choose the level that best describes a typical week.
Calories for weight loss or gain
A rule of thumb is that eating roughly 500 calories a day below maintenance leads to about 1 pound (0.5 kg) of loss per week, and 250 calories below leads to about half of that. Real results vary, because your body adapts and weight also moves with water and other factors. A slow, steady pace is easier to keep up and helps you hold on to muscle. Most health organizations suggest aiming for about 1 to 2 pounds (0.5 to 1 kg) a week at most.
Safety first
- Eating less than about 1,200 calories (women) or 1,500 calories (men) a day is generally not recommended without medical supervision.
- Very low intakes make it harder to get enough protein, fiber and micronutrients.
- This tool is for adults. It is not for pregnancy, breastfeeding, children, or anyone with a medical condition that affects metabolism.
Make your calories work harder
- Fill your plate with fiber-rich foods that keep you full. See our fiber guide and healthy snacking ideas.
- Start the day with a filling meal using our healthy breakfast ideas.
- Split your calories into carbs, protein and fat with the macro calculator.
- Check you are getting enough protein with the protein calculator.
Frequently asked questions
How many calories do I need to lose weight?
Start from your maintenance calories and subtract about 250 to 500 a day for gentle, steady loss. Check your progress after two to three weeks and adjust.
Is 1,200 calories enough?
For most adults it is too low to sustain, and it is generally the minimum floor used in guidance for women, with 1,500 for men. Anything lower should be supervised by a healthcare professional.
Why has my weight stopped changing?
As you lose weight, your calorie needs fall, and day-to-day water changes can hide progress. Re-run the calculator with your new weight and be patient for a few weeks before changing anything.
How accurate is a calorie calculator?
It is an estimate. Individual needs can differ by 10 to 15 percent from the formula, so treat the result as a starting point and adjust based on how your weight responds.
More free health calculators
Quick, private tools that run in your browser.
This calculator provides general estimates for healthy adults and is for information only. It is not medical advice and does not replace a conversation with a qualified healthcare professional. Read our disclaimer and editorial policy.