Daily calorie target for your goal — weight & height in any unit.
BMR (male) = 10W + 6.25H − 5A + 5 BMR (female) = 10W + 6.25H − 5A − 161 TDEE = BMR × AM
This calculator uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for estimating Basal Metabolic Rate (BMR) in healthy adults. BMR is the number of calories your body burns at complete rest to sustain basic functions. Your TDEE (Total Daily Energy Expenditure) is then calculated by multiplying BMR by an Activity Multiplier that accounts for your lifestyle.
Step 1 — Calculate BMR:
Step 2 — Multiply by Activity Level to get TDEE: TDEE = BMR × Activity Multiplier
BMR = (10 × 68) + (6.25 × 165) − (5 × 30) − 161 BMR = 680 + 1031.25 − 150 − 161 BMR = 1400.25 kcal/day TDEE = 1400.25 × 1.55 TDEE ≈ 2170 kcal/day
Result: **Maintenance Calories: ~2,170 kcal/day** - For weight loss (−0.5 kg/week): ~1,670 kcal/day - For weight gain (+0.5 kg/week): ~2,670 kcal/day
A result of ~2,170 kcal/day means this woman needs approximately 2,170 calories daily to maintain her current weight at a moderately active lifestyle. To lose roughly 0.5 kg (1 lb) per week, she would target a 500 kcal/day deficit, eating around 1,670 kcal/day. To gain weight at the same rate, she would add 500 kcal/day for a total of 2,670 kcal/day. These figures are estimates; individual metabolism, muscle mass, and hormonal factors can cause real-world variation.
⚕️ Disclaimer: This calculator is for educational purposes only and does not constitute medical or nutritional advice. Consult a registered dietitian or physician before making significant changes to your diet, especially if you have a medical condition.
A calorie (technically a kilocalorie, kcal) is a unit of energy. Food provides energy in the form of calories, and your body uses that energy to power everything from breathing to exercise.
The Mifflin-St Jeor equation (1990) has been validated in numerous studies and is recommended by the Academy of Nutrition and Dietetics as the most accurate predictive equation for healthy adults. Older formulas like Harris-Benedict (1919) tend to overestimate calorie needs.
| Level | Description | Multiplier | |---|---|---| | Sedentary | Desk job, little or no exercise | 1.20 | | Lightly Active | Light exercise 1–3 days/week | 1.375 | | Moderately Active | Moderate exercise 3–5 days/week | 1.55 | | Very Active | Hard exercise 6–7 days/week | 1.725 | | Extra Active | Physical job or twice-daily training | 1.90 |
The Mifflin-St Jeor equation estimates BMR from population-level averages. It does not account for body composition (muscle vs. fat), specific medical conditions, medications, or hormonal status. Actual needs may differ by ±10%.
BMR (Basal Metabolic Rate) is the calories your body needs at complete rest. TDEE (Total Daily Energy Expenditure) adds the calories burned through all physical activity, digestion, and daily movement on top of BMR. TDEE is the number you should actually use to plan your diet.
Online calorie calculators based on the Mifflin-St Jeor equation are accurate within roughly ±10% for most healthy adults. They are population-average predictions and cannot account for individual metabolic variation, medical conditions, or body composition. Indirect calorimetry (metabolic testing) in a clinical setting is the most precise measurement.
Eating significantly below your BMR for extended periods can cause muscle loss, nutrient deficiencies, hormonal disruption, fatigue, and a slowdown of your metabolism (adaptive thermogenesis). It is generally recommended to stay above 1,200 kcal/day for women and 1,500 kcal/day for men without medical supervision.
Calorie needs generally decrease with age. After age 30, BMR tends to drop by roughly 1–2% per decade, largely due to a natural reduction in muscle mass (sarcopenia). This is why the formula subtracts 5 × age — older individuals have a lower estimated metabolic rate.
The Mifflin-St Jeor equation (1990) is generally considered more accurate for modern, healthy adults. Multiple validation studies show it predicts resting metabolic rate within about 10% for most people. The older Harris-Benedict equation (1919, revised 1984) tends to overestimate BMR by roughly 5%.
One kilogram of body fat contains roughly 7,700 kcal. To lose 1 kg per week, you need a daily calorie deficit of about 1,100 kcal (7,700 ÷ 7). Many dietitians consider this aggressive; a deficit of 500–750 kcal/day (0.5 kg/week) is typically safer and more sustainable.
No. The Mifflin-St Jeor equation does not use body fat percentage. For a more body-composition-aware estimate, the Katch-McArdle formula uses lean body mass and may be more accurate for athletes or very muscular individuals.
Yes. To build muscle you generally need a caloric surplus of 250–500 kcal above your TDEE, combined with adequate protein (1.6–2.2 g per kg of body weight) and a progressive resistance-training program. Eating at a surplus without training tends to increase fat rather than muscle.
This calculator is not designed for pregnant or breastfeeding individuals, as calorie requirements change significantly during these stages. Please consult your OB-GYN or a registered dietitian for personalized guidance.
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