Calculate how many calories you need per day based on age, sex, weight, height, and activity level. Get your TDEE with goal-based adjustments.
Your daily calorie needs — also called Total Daily Energy Expenditure (TDEE) — are an estimate of the calories you use each day through resting metabolism, activity, and the thermic effect of food. It is a starting point for maintenance, fat loss, or weight gain planning, not a precise measurement.
This worksheet compares several common BMR formulas (Mifflin-St Jeor, Harris-Benedict, Katch-McArdle, and Cunningham) and applies an activity factor so you can see how the estimate changes with different assumptions. Mifflin-St Jeor is the default because it is a common general-population starting point; body-fat-based formulas can be more specific when lean mass is known.
Guessing your calorie needs often leads to bigger corrections than necessary. A calculated TDEE gives you a structured starting point that you can refine over time without pretending the number is exact.
TDEE = BMR × Activity Factor BMR Formulas: • Mifflin-St Jeor: 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161 (F) or + 5 (M) • Harris-Benedict (revised): 447.593 + 9.247 × weight(kg) + 3.098 × height(cm) − 4.330 × age (F); 88.362 + 13.397 × weight(kg) + 4.799 × height(cm) − 5.677 × age (M) • Katch-McArdle: 370 + 21.6 × lean mass(kg) • Cunningham: 500 + 22 × lean mass(kg) Activity Factors: Sedentary: 1.2 | Light: 1.375 | Moderate: 1.55 | Active: 1.725 | Extra Active: 1.9
Result: 2,740 calories/day
Using Mifflin-St Jeor for a 30-year-old male, 178 cm, 80 kg: BMR = 10(80) + 6.25(178) − 5(30) + 5 = 800 + 1112.5 − 150 + 5 = 1,767.5 kcal. With a moderate activity factor of 1.55: TDEE = 1,767.5 × 1.55 = 2,740 kcal/day. This is the estimated number of calories needed to maintain current weight.
Your body expends energy through resting metabolism, activity, and the thermic effect of food. TDEE is the combined estimate of those components. For most people, the activity factor is the part that changes the estimate the most.
Mifflin-St Jeor is a common default for general use. Harris-Benedict remains widely recognized, while Katch-McArdle and Cunningham can be more useful when body fat percentage is known and lean mass differs meaningfully from average assumptions. Comparing formulas can be more informative than assuming one equation is always best.
No calorie formula perfectly captures daily movement, training load, appetite, or metabolic variation. Use the result as a starting point, hold intake steady for a couple of weeks when possible, then adjust based on weight trend, energy, hunger, and performance.
For fat loss or weight gain, smaller adjustments are usually easier to evaluate than aggressive swings in intake. A calculator can suggest a reasonable direction, but the best long-term target is the one that matches your real-world response.
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This worksheet estimates daily energy needs by taking a predictive BMR equation, multiplying it by an activity factor, and then adjusting the result for the selected goal. It is a planning estimate only: it depends on the chosen formula, the activity category, and the person's actual body composition and movement pattern, so real-world weight trend is the final check.
It depends on your age, sex, size, and activity level. Most adult men need 2,200–3,000 calories/day and most adult women need 1,800–2,400 calories/day for maintenance. This calculator provides a personalized estimate based on your specific inputs. Adjust based on whether your goal is weight loss, gain, or maintenance.
Mifflin-St Jeor is a common general-population starting estimate. If you know your body fat percentage, the Katch-McArdle formula may be more informative because it uses lean body mass, which can better reflect differences in body composition.
Sedentary: desk job, minimal exercise. Light: 1–3 days/week of light exercise. Moderate: 3–5 days/week of moderate exercise. Active: 6–7 days/week of hard exercise or physical job. Extra active: intense daily training or very physically demanding job. When in doubt, choose one level lower than you think.
The TDEE method already accounts for exercise in the activity multiplier, so you don't need to add exercise calories on top. If you track exercise calories separately (like with a fitness tracker), be cautious — devices often overestimate calorie burn by 15–30%. Eating back half of tracked exercise calories is a safer approach.
Fitness trackers use heart rate and motion data to estimate calorie burn, while TDEE formulas use statistical equations. Both are estimates with margins of error (typically ±10–15%). If they disagree significantly, use the average of both and adjust based on real-world weight trends over 2–4 weeks.
A deficit of about 500 calories per day is often used as a rule of thumb, but the real rate varies from person to person. Most people do better with a pace they can maintain consistently rather than treating the calculator output as a fixed target.
The TDEE method averages your activity over the week, so the same daily intake works for most people. However, some prefer calorie cycling — eating more on training days and less on rest days while keeping the weekly total the same. Both approaches can be effective.
Yes, but less dramatically than commonly believed. BMR decreases about 1–2% per decade after age 20, primarily due to loss of lean muscle mass. Maintaining muscle through resistance training can significantly offset this decline. The age factor in BMR formulas accounts for this average decrease.