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Calorie Calculator

Find out how many calories you need per day to lose weight, maintain, or build muscle — based on your age, sex, height, weight, and activity level.

Units
Sex

Your Results

kcal
Daily Calorie Target
Enter your details above to calculate
Weight Loss
kcal/day · −0.5 kg/week
Maintenance
kcal/day
Weight Gain
kcal/day · +0.5 kg/week

Suggested Macros

Protein (30%)
g/day
Carbs (40%)
g/day
Fat (30%)
g/day

Your BMR

kcal
Basal Metabolic Rate
Calories burned at complete rest (Mifflin-St Jeor)

These estimates use the Mifflin-St Jeor equation — considered the most accurate formula for the general population. Individual needs vary based on muscle mass, metabolism, genetics, and health conditions. Consult a dietitian for personalized guidance.

How Many Calories Do You Need?

The number of calories you need each day depends on several factors: your age, sex, weight, height, and how physically active you are. There is no single answer that works for everyone — a 25-year-old male athlete needs significantly more calories than a 60-year-old sedentary woman.

Did you know? The Dietary Guidelines for Americans estimate adults need 1,600–3,000 kcal/day — but individual needs can vary by ±600 kcal due to differences in muscle mass, genetics, and NEAT (Non-Exercise Activity Thermogenesis).

According to the Dietary Guidelines for Americans, the average adult needs between 1,600 and 3,000 calories per day. Women typically need 1,600–2,400 kcal and men need 2,000–3,000 kcal, depending on age and activity level. These are broad estimates — the calculator above gives you a personalized number based on the Mifflin-St Jeor equation.

Your body uses calories for three main purposes: basal metabolism (keeping organs, brain, and cells functioning at rest), the thermic effect of food (digesting what you eat), and physical activity (everything from walking to intense exercise). Of these, basal metabolism accounts for the largest share — typically 60–75% of your total daily burn.

The Mifflin-St Jeor Equation

Published in 1990, the Mifflin-St Jeor equation is widely regarded as the most accurate formula for estimating Basal Metabolic Rate (BMR) in healthy adults. It replaced the older Harris-Benedict equation (1919) and is recommended by the Academy of Nutrition and Dietetics.

Men (Metric)
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Example: 10 × 80 + 6.25 × 180 − 5 × 30 + 5 = 1,780 kcal
Women (Metric)
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Example: 10 × 65 + 6.25 × 165 − 5 × 28 − 161 = 1,390 kcal

Once you know your BMR, multiply it by an activity factor to get your TDEE (Total Daily Energy Expenditure) — the number of calories you actually burn in a day including all movement and exercise.

Understanding Activity Levels

Your activity level multiplier has a huge impact on your calorie needs. Someone who exercises daily can burn 500–1,000 more calories than a sedentary person of the same size. Choose the level that best matches your typical week:

Common mistake: People tend to overestimate their activity level by one category. A 2019 study found that self-reported "moderately active" individuals were actually lightly active when measured with accelerometers.
LevelDescriptionMultiplier
SedentaryDesk job, little or no exercise1.2
Lightly ActiveLight exercise or sports 1–3 days/week1.375
Moderately ActiveModerate exercise 3–5 days/week1.55
Very ActiveHard exercise or sports 6–7 days/week1.725
Extra ActivePhysical job or training 2× per day1.9

Tips for Your Calorie Goal

  • For weight loss: Aim for a 500 kcal/day deficit — this translates to roughly 0.5 kg (1 lb) of fat loss per week. Avoid going below 1,200 kcal (women) or 1,500 kcal (men) without medical supervision.
  • For maintenance: Eat at your TDEE and adjust based on weekly weigh-ins. If your weight creeps up or down, add or subtract 100–200 kcal.
  • For weight gain: A surplus of 250–500 kcal/day supports muscle growth when paired with strength training. Larger surpluses mainly add body fat.
  • Prioritize protein: Aim for 1.6–2.2 g per kg of bodyweight daily. Protein helps preserve muscle during a deficit and supports growth during a surplus.
  • Track consistently: Logging meals for even a few weeks builds awareness of portion sizes and calorie density, which helps whether you continue tracking or not.
  • Be patient: Weight fluctuates daily due to water, sodium, and digestion. Focus on weekly averages rather than any single day.
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