About Calorie Calculator
Calculate your daily calorie needs based on age, weight, height, and activity level. Get your TDEE, BMR, and targets for weight loss, maintenance, or muscle gain. Free.
How to use
- Enter your age, gender, height, and current weight. These four inputs determine your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest just to maintain basic functions like breathing, circulation, and cell repair. BMR accounts for 60-75% of your total daily calorie burn.
- Select your activity level honestly. Sedentary means desk job with minimal walking. Lightly active means 1-3 days of light exercise per week. Moderately active means 3-5 days of moderate exercise. Very active means hard exercise 6-7 days per week. Overestimating activity level is the most common reason calorie calculators give inaccurate results.
- View your BMR (resting calories) and TDEE (Total Daily Energy Expenditure). TDEE is your BMR multiplied by an activity factor and represents the total calories you burn in a typical day. This is the number that matters for weight management — eat below it to lose weight, above it to gain.
- Review the calorie targets for your goal. For weight loss: a 500 calorie daily deficit produces roughly 1 lb of weight loss per week. For maintenance: eat at your TDEE. For muscle gain: a 250-500 calorie surplus supports lean mass growth with minimal fat gain.
- Adjust your activity level to see how exercise changes your calorie needs. Moving from sedentary to moderately active can increase TDEE by 400-600 calories per day. This illustrates why combining diet and exercise is more effective than diet alone.
- Use the macronutrient breakdown as a starting guide for meal planning. A balanced approach for most people is 30% protein, 35% carbs, 35% fats, adjusted based on your specific goals and dietary preferences.
Frequently asked questions
What is TDEE?
TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a 24-hour period, including all activity. It combines your BMR (resting metabolism), the thermic effect of food (calories burned digesting meals, roughly 10% of intake), non-exercise activity thermogenesis (NEAT — fidgeting, walking, standing), and exercise activity. A sedentary 30-year-old woman weighing 140 lbs has a TDEE of approximately 1,750 calories. A moderately active 30-year-old man weighing 180 lbs has a TDEE of approximately 2,600 calories. Knowing your TDEE is the foundation of any nutrition plan.
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest — if you stayed in bed all day doing absolutely nothing. It fuels breathing, heart function, brain activity, cell repair, and temperature regulation. TDEE is BMR plus all activity calories. For a sedentary person, TDEE is roughly 1.2x BMR. For a very active person, TDEE can be 1.7-1.9x BMR. A man with a BMR of 1,800 might have a TDEE of 2,160 (sedentary) to 3,400 (very active). BMR alone is not useful for diet planning because nobody stays at complete rest all day.
How many calories should I eat to lose weight?
A safe and sustainable rate of weight loss is 1-2 lbs per week, which requires a daily deficit of 500-1,000 calories below your TDEE. For most people, a 500 calorie deficit is achievable without extreme hunger or muscle loss. Never drop below 1,200 calories (women) or 1,500 calories (men) without medical supervision, as very low calorie diets risk nutrient deficiencies, muscle loss, and metabolic slowdown. For someone with a TDEE of 2,200: eating 1,700 calories daily creates a 500 calorie deficit and results in about 1 lb of weight loss per week, or roughly 50 lbs in a year.
Which calorie formula is most accurate?
The Mifflin-St Jeor equation is considered the most accurate for most adults, predicting BMR within 10% for about 82% of people. The Harris-Benedict equation (original 1919 or revised 1984) slightly overestimates BMR for many people. The Katch-McArdle formula is most accurate when you know your body fat percentage, as it uses lean body mass instead of total weight — use the
Body Fat Calculator to get your body fat percentage if you want to use Katch-McArdle. For practical purposes, the difference between formulas is typically 50-100 calories. Use any reputable formula as a starting point, then adjust based on real-world results after 2-3 weeks of consistent tracking.
Should I eat back exercise calories?
It depends. If you calculated your TDEE using an activity level that already includes exercise, then no — your target already accounts for those calories. If you set your TDEE as sedentary and then exercise on top, you should eat back some exercise calories (50-75% of estimated burn, since calorie trackers and gym machines typically overestimate by 20-30%). For weight loss, eating back too many exercise calories can erase your deficit. For athletes and those training intensely, undereating after hard workouts impairs recovery and performance. As a general rule, eat back half of estimated exercise calories.
How do I count calories accurately?
Three keys to accurate tracking: (1) Use a food scale, not measuring cups — a 'cup of rice' can vary by 30-50% in calories depending on how tightly packed it is. (2) Track everything, including oils used in cooking (1 tablespoon of olive oil is 120 calories), sauces, beverages, and small bites that add up. (3) Use a comprehensive food database app like MyFitnessPal or Cronometer that includes verified entries. You do not need to count calories forever — most people develop accurate portion intuition after 3-6 months of consistent tracking and can maintain results without a food scale.
Does metabolism slow with age?
Yes, but less than commonly believed. Recent research published in Science (2021) found that metabolism is stable from age 20-60, declining only about 0.7% per year. The bigger factor is that adults tend to lose muscle mass (1-2% per decade after 30) and become less physically active with age, both of which reduce TDEE. A 50-year-old with the same muscle mass and activity level as a 25-year-old burns nearly the same calories. The practical takeaway: resistance training and staying active are far more important for maintaining metabolism than any supplement or 'metabolism-boosting' food.
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