Daily Calorie Calculator

How to Use the Calorie Calculator

1. Select biological sex and enter age, height and current weight.
2. Choose the activity level that best matches your typical week.
3. Pick a goal: maintain, lose or gain weight. For lose or gain, choose a pace in kg per week and, if you like, a target weight.
4. Review your daily calories, BMR, maintenance calories, the daily change and the time to your target, and use them as a starting point for meal planning.

Select your sex and enter your age in years, height in centimetres and weight in kilograms. Choose the activity level that matches a typical week, not your best week. With the goal set to Maintain, the result is your maintenance estimate (your TDEE). For Lose or Gain, choose a pace of 0.25, 0.5, 0.75 or 1 kg a week: the calculator subtracts or adds the matching daily amount, and a target weight gives you an estimate in weeks. The pace and target weight fields are only used for Lose and Gain. You always see your BMR too, the energy your body uses at rest.

Calorie Calculator Formula Explained

BMR for men is calculated as (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5. For women the final constant is −161 instead of +5. TDEE is then BMR multiplied by an activity factor (typically 1.2 sedentary to 1.9 very active). The Mifflin-St Jeor equation is preferred over older Harris-Benedict formulas for modern populations because it was derived from more recent data and tends to overestimate less.

The calculator first finds your BMR with the Mifflin-St Jeor equation. It then multiplies BMR by the activity factor you picked: 1.2, 1.375, 1.55, 1.725 or 1.9. For a weight goal it uses the common approximation that one kilogram of body weight is worth about 7,700 kcal. A pace of 0.5 kg a week therefore means 0.5 × 7,700 ÷ 7 = 550 kcal a day below (Lose) or above (Gain) your maintenance calories. The time to your target is the difference between your current and target weight divided by the pace, rounded up to whole weeks. Your energy needs change as your weight changes, so real progress is rarely this steady and the time is a guide. All numbers are rounded to whole calories when shown. The equation was built from data on adults, so it is not suitable for children, and it cannot see muscle mass, so very muscular or very lean people may differ from the estimate. The equation comes from a 1990 study by Mifflin and colleagues in the American Journal of Clinical Nutrition, which studied 498 healthy adults aged 19 to 78.

Calorie Calculator Example Calculation

A 30-year-old woman, 165 cm, 62 kg, moderately active, has a maintenance estimate near 2,077 kcal. Aiming to lose 0.5 kg a week brings that down by 550 kcal to about 1,527 kcal a day, which is still above her BMR of 1,340. Recalculate after a notable weight change so the estimate stays current.

Worked example: choose Female, age 30, height 165 cm, weight 62 kg and Moderate (3–5 days/week). BMR is 10 × 62 + 6.25 × 165 − 5 × 30 − 161 = 1,340 calories. Multiplied by 1.55, the estimated daily calories are 2,077. For a man aged 30, 180 cm and 80 kg with the Light activity level, BMR is 1,780 and the daily estimate is 2,448. Now set the woman’s goal to Lose, the pace to 0.5 kg a week and the target weight to 57 kg. The daily calories become 1,527 (2,077 − 550), the daily change is −550 and the 5 kg to lose takes about 10 weeks. For the man, a Gain goal at 0.25 kg a week adds 275 kcal and gives 2,723 calories a day.

When to use this tool

Use this to set a daily energy baseline for weight management, sports nutrition or general health. Adjust for your real activity, not an idealised schedule. Choose Lose or Gain when you want to turn a pace in kilograms per week into a daily target; if you only want maintenance calories with fixed 10% and 20% cuts, the TDEE calculator does that. This is an estimate, not medical advice. If you have a medical condition, are pregnant or plan a big change to your diet, talk to a doctor or registered dietitian first.

Key Features & Benefits of This Calorie Calculator

• Mifflin-St Jeor equation — BMR is worked out from your sex, age, height and weight, then multiplied by an activity factor.
• Five activity levels — from sedentary (×1.2) to very active (×1.9), so the estimate matches your real week, not your best week.
• Goal and pace in kg per week — choose maintain, lose or gain at 0.25, 0.5, 0.75 or 1 kg a week and see the daily calorie target and the daily change.
• Time to target weight — enter a target weight to see an estimate in weeks; in the example, 5 kg at 0.5 kg a week is about 10 weeks.
• Target, BMR and maintenance together — see the target for your goal next to the calories you burn in a day (your TDEE) and the energy your body uses at rest.
• Safety checks — a note appears if a weight-loss target is under 1,200 kcal a day or below your BMR.
• Instant, free and private — runs entirely in your browser, no sign-up, nothing stored.

Calorie Calculator — FAQs

Sources and review

Sources last checked: 9 October 2026. These sources give the background for this calculator. They are general information and do not replace advice from a doctor, midwife or registered dietitian.

• NHS: Understanding calories: an average man needs about 2,500 kcal a day and an average woman about 2,000, and needs vary with age, weight, height and activity.
• Mifflin et al. (1990), American Journal of Clinical Nutrition: the resting energy expenditure equation this calculator uses.
• CDC: Steps for losing weight: people who lose weight at a gradual, steady pace of about 1 to 2 pounds a week are more likely to keep the weight off.

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