How many calories should I eat a day?
The recommended calorie intake, or TDEE (Total Daily Energy Expenditure), depends on many factors: your age, height, weight, sex, and physical activity level. Our calorie calculator uses the Mifflin-St Jeor equation to estimate your daily calorie needs as accurately as possible.
For example, a 40-year-old man with an active physical job (equivalent to exercising six days a week) and average American measurements (5 ft 9 in, 194.7 lbs) should consume about 3,567 calories per day. Meanwhile, an average 18-year-old girl (5 ft 4 in, 117 lbs) who exercises once a week only needs 1,814 calories per day — over a thousand fewer than her father.
What are calories?
Calories are measures of energy. In nutrition, we use kilocalories (kcal), where 1 kcal equals 4.18 kJ. Each food macronutrient provides a different amount of energy per gram:
- Carbohydrates: 4 kcal/g
- Protein: 4 kcal/g
- Fat: 9 kcal/g
How our calorie calculator works
The calculator is based on the Mifflin-St Jeor equation, which calculates your Basal Metabolic Rate (BMR) — the energy your body needs at complete rest:
- 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 get your TDEE:
- Sedentary (little or no exercise): × 1.2
- Slightly active (light exercise 1–2 days/week): × 1.4
- Moderately active (moderate exercise 2–3 days/week): × 1.6
- Very active (hard exercise 4–5 days/week): × 1.75
- Extra active (very hard exercise or physical job 6–7 days/week): × 2.0
- Professional athlete: × 2.3
Calorie goals for weight management
Once you know your TDEE (maintenance calories), you can adjust your intake based on your goal:
- Lose weight: eat ~500 kcal/day less than your TDEE → lose ~0.5 kg/week
- Maintain weight: eat exactly your TDEE
- Gain weight: eat ~500 kcal/day more than your TDEE → gain ~0.5 kg/week
Trying to lose weight? Eat eggs!
Eggs are one of the best foods for a calorie-controlled diet. They are nutrient-dense, low in calories, and highly filling:
- A small egg (38 g): ~54 kcal
- A medium egg (44 g): ~63 kcal
- A large egg (50 g): ~72 kcal (yolk: ~55 kcal, white: ~17 kcal)
Each egg provides ~6 g of complete protein (all 9 essential amino acids), healthy fats, and key vitamins (A, D, E, K, B12), iron, selenium, choline, and antioxidants. One or two eggs per day is perfectly healthy for most people.
What to eat to lose weight
When reducing calories, focus on nutrient-dense, satiating foods:
- Proteins: eggs, chicken breast, fish, legumes, Greek yogurt
- Vegetables: leafy greens, broccoli, cucumbers, peppers (high volume, low calories)
- Whole grains: oats, quinoa, brown rice (fiber keeps you full longer)
- Healthy fats: avocado, nuts, olive oil (in moderation)
Avoid ultra-processed foods, sugary drinks, and foods high in refined carbohydrates — they are calorie-dense but provide little satiety.
Frequently Asked Questions (FAQs)
Is the calorie calculator accurate?
The Mifflin-St Jeor equation is considered the most accurate formula for estimating calorie needs in healthy adults. However, individual factors like metabolism, hormones, and overall health can affect real-world results. Use the result as a starting guideline and adjust based on your progress over 2–4 weeks.
How many calories should I eat to lose weight?
A deficit of 500 kcal/day leads to a weight loss of approximately 0.5 kg (1 lb) per week, which is considered a safe and sustainable rate. Avoid going below 1,200 kcal/day for women or 1,500 kcal/day for men without medical supervision.
Does physical activity level really matter?
Yes — it's one of the biggest factors. A sedentary person with the same body measurements as a professional athlete may need almost twice fewer calories per day. If unsure, choose a lower activity level to avoid overestimating your needs.
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest to maintain basic vital functions (breathing, circulation, cell repair). TDEE (Total Daily Energy Expenditure) is your BMR multiplied by your activity level — it represents the total calories you burn in a day.