Calorie Calculator.
Find your daily calorie target for weight loss, maintenance, or muscle gain based on your body stats and activity level.
Daily Target
kcal / day
BMR (at rest)
kcal
Maintenance
kcal (TDEE)
Protein
30% of cals
Carbs
40% of cals
Fat
30% of cals
Runs entirely in your browser. The values you enter never leave your device — there is no request to our server and nothing is stored. How we handle data
How Calorie Needs Are Calculated
Your daily calorie requirement depends on your resting metabolic rate (BMR), how active you are (TDEE), and your weight goal. This calculator uses the Mifflin-St Jeor equation — the formula validated by the Academy of Nutrition and Dietetics as the most accurate for modern adults.
Mifflin-St Jeor Equation
Women: BMR = (10 × kg) + (6.25 × cm) − (5 × age) − 161
TDEE = BMR × Activity Factor
Target = TDEE ± Goal Adjustment
Calorie Adjustments by Goal
Weight Loss
1 lb of body fat ≈ 3,500 calories. A 500-calorie daily deficit produces roughly 1 lb/week of fat loss. A 250-calorie deficit (0.5 lb/week) is more sustainable and better preserves muscle. Avoid deficits over 1,000 calories/day without medical supervision.
Muscle Gain
A 250–500 calorie daily surplus supports lean muscle growth when combined with resistance training. Protein intake of 1.6–2.2g/kg of bodyweight is essential during a building phase. Exceeding 500 calories above TDEE tends to increase fat accumulation alongside muscle.
Internal Navigation
Daily Calorie Intake: Formula and How to Use It Methodology.
The Calculation Branch
Industrial Standards.
The Mifflin-St Jeor equation (1990) outperforms the older Harris-Benedict formula in clinical accuracy. A 2005 study in the Journal of the American Dietetic Association confirmed it is the most accurate predictor of resting metabolic rate for most adults. Activity multipliers: Sedentary 1.2, Light 1.375, Moderate 1.55, Active 1.725, Extra Active 1.9.
In-Depth Analysis & Reference Data
The macro split of 30% protein / 40% carbs / 30% fat is a balanced general-purpose starting point. Each gram of protein and carbohydrate provides 4 kcal; each gram of fat provides 9 kcal. Athletes and bodybuilders often push protein to 35–40% of calories and lower carbs accordingly. For weight loss, higher protein (35%+) preserves muscle mass during a calorie deficit.
Registry Questions & FAQ.
Why am I not losing weight at a 500-calorie deficit?
Common causes: inaccurate food tracking (underestimating portions), overestimated activity level, metabolic adaptation, or water retention masking fat loss. Weigh food with a scale rather than estimating by volume, and allow 4–6 weeks before adjusting your target.
Should I eat back exercise calories?
If your chosen activity level already includes your exercise (e.g., Very Active), do not eat back exercise calories — they are already factored in. If you selected Sedentary and exercise separately, eating back 50–75% of exercise calories is a reasonable adjustment.
Estimates for planning. Always confirm against an authoritative source.