Calorie Intake Calculator

Subtract 500 kcal from your maintenance calories (TDEE) to lose approximately 0.5 kg per week. For a person with a TDEE of 2,200 kcal, eating 1,700 kcal per day creates the required deficit. Deficits larger than 1,000 kcal per day are not recommended without medical supervision as they increase muscle loss and nutritional deficiencies.

The Mifflin-St Jeor equation (1990) is currently the most widely validated BMR formula for general adults. For men: BMR = 10 times weight (kg) + 6.25 times height (cm) minus 5 times age + 5. For women: BMR = 10 times weight (kg) + 6.25 times height (cm) minus 5 times age minus 161. Studies comparing multiple formulas consistently find Mifflin-St Jeor has the smallest average error versus measured metabolic rate.

TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor. The five standard activity multipliers are: Sedentary 1.2, Lightly Active 1.375, Moderately Active 1.55, Very Active 1.725, Extra Active 1.9. For example, a man with a BMR of 1,800 kcal at a Moderately Active level has a TDEE of 1,800 times 1.55 = 2,790 kcal per day.

A calorie surplus of 250 to 500 kcal above your TDEE supports muscle growth. This calculator adds 300 kcal above maintenance for the Gain goal, producing roughly 0.1 to 0.2 kg of lean mass per week when combined with resistance training. Larger surpluses add more fat alongside muscle. Protein intake of at least 1.6 g per kg of body weight per day is essential for maximising muscle protein synthesis.

BMR formulas estimate within plus or minus 10 to 15 percent of measured resting metabolic rate for most adults. The activity multiplier introduces additional uncertainty since people tend to overestimate their activity level. Treat the output as a starting estimate. Track your actual weight weekly for 2 to 3 weeks, then adjust the calorie target by 100 to 200 kcal if results do not match expectations.

Macros (macronutrients) are protein, carbohydrates, and fat. For the Lose goal, this calculator uses 35% protein, 35% carbs, 30% fat. For Maintain: 25% protein, 45% carbs, 30% fat. For Gain: 30% protein, 45% carbs, 25% fat. To convert calories to grams: protein 4 kcal per gram, carbs 4 kcal per gram, fat 9 kcal per gram. Higher protein allocations during a deficit help preserve lean muscle mass.

Sedentary: desk job, walks very little, no planned exercise. Lightly Active: office job plus 1 to 3 days per week of exercise. Moderately Active: moderate exercise 3 to 5 days per week, or a moderately physical job. Very Active: hard training 6 to 7 days per week, such as competitive athletes. Extra Active: both a physically demanding job and daily hard training. Most people who go to the gym a few times per week are Lightly Active.

Yes. As your body weight decreases, your BMR decreases because there is less tissue to maintain. After losing 5 kg, recalculate your calorie target to avoid a plateau. Similarly, as you gain muscle (which is denser than fat), your BMR and TDEE both increase slightly. Recalculating every 4 to 6 weeks or every 3 to 5 kg of weight change keeps the target accurate.

This calculator enforces a floor of 1,200 kcal per day regardless of the calculation result. Eating below 1,200 kcal for extended periods risks nutrient deficiencies, metabolic adaptation, and muscle loss. The National Institutes of Health recommends not going below 800 kcal per day without medical supervision. For individuals with very low TDEE (petite, sedentary women), a small deficit may not be achievable while staying above 1,200 kcal.

The per-meal field divides your daily target by three (three meals per day). For 1,800 kcal per day, each meal would contain about 600 kcal. If you eat 4 or 5 meals per day, divide your daily total by that number. For a 250 kcal snack, subtract it from the daily total first, then divide the remainder across meals. Consistent portion control over weeks matters more than hitting exact targets on any single day.

Common reasons: you may be selecting an activity level that is too high (the most common overestimate), your age reduces BMR over time, or your height and weight combination differs from average. Taller and heavier people have higher TDEE; shorter, lighter people have lower TDEE. Women have lower TDEE than men of the same stats due to the 166 kcal difference in the Mifflin-St Jeor formula and on average lower muscle mass.

NEAT is the energy burned from all movement other than formal exercise: walking, standing, fidgeting, taking stairs, cleaning. NEAT varies by up to 2,000 kcal per day between individuals with the same formal exercise schedule. It is the biggest source of individual variation in TDEE. If your weight is not changing at the calculated intake, check whether your daily movement (steps, standing) is higher or lower than average, and adjust your activity multiplier accordingly.