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🍽️ Nutrition Guide 6 min read

How Many Calories Should I Eat Per Day?

There is no single universal calorie target — the right number depends on your body weight, height, age, sex and how active you are. This guide explains how daily calorie needs are calculated, gives you reference numbers to work from, and covers how to adjust depending on your goal.

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BMR and TDEE: the two numbers that matter

Your daily calorie needs come from two components. BMR (Basal Metabolic Rate) is the energy your body needs at complete rest — just to keep your heart beating, lungs breathing and organs functioning. TDEE (Total Daily Energy Expenditure) is BMR multiplied by an activity factor to account for movement, exercise and daily life.

~60–70%
Of TDEE that typically comes from BMR alone
~15–30%
From daily non-exercise movement (NEAT)
~5–10%
From digesting food (thermic effect)
500 kcal
Approx. deficit for ~0.5 kg/week fat loss

How BMR is estimated: the Mifflin–St Jeor formula

The Mifflin–St Jeor equation is the most widely validated formula for estimating BMR in healthy adults. It uses weight, height and age:

Men: BMR = (10 × kg) + (6.25 × cm) − (5 × age) + 5
Women: BMR = (10 × kg) + (6.25 × cm) − (5 × age) − 161

Example — 30-year-old woman, 65 kg, 168 cm:
BMR = (10 × 65) + (6.25 × 168) − (5 × 30) − 161 = 650 + 1,050 − 150 − 161 = 1,389 kcal/day

To get TDEE, multiply by an activity factor (see table below). For this person at a lightly active level: 1,389 × 1.375 = ~1,910 kcal/day to maintain weight.

Activity multiplier table

Multiply your BMR by the appropriate factor to estimate your TDEE. Be honest about your activity level — most people overestimate how active they are on a typical day.

Activity levelDescriptionMultiplier
SedentaryDesk job, little or no exercise× 1.20
Lightly activeLight exercise 1–3 days/week× 1.375
Moderately activeModerate exercise 3–5 days/week× 1.55
Very activeHard exercise 6–7 days/week× 1.725
Extra activePhysical job + daily training× 1.90

Calorie targets by body weight and goal

The table below provides rough TDEE estimates for a moderately active adult at different body weights, along with adjusted targets for fat loss and muscle gain. Values are approximate and assume average height for each weight range.

Body weightMaintenance (TDEE)Fat loss (−500 kcal)Muscle gain (+200 kcal)
55 kg~1,850 kcal~1,350 kcal~2,050 kcal
65 kg~2,050 kcal~1,550 kcal~2,250 kcal
75 kg~2,250 kcal~1,750 kcal~2,450 kcal
85 kg~2,450 kcal~1,950 kcal~2,650 kcal
95 kg~2,650 kcal~2,150 kcal~2,850 kcal
105 kg~2,850 kcal~2,350 kcal~3,050 kcal
These are estimates for moderately active adults. Sedentary individuals should subtract 200–300 kcal from maintenance figures. Very active individuals should add 300–500 kcal. Use a full calculator for a personalised number.

Calorie targets by goal

Once you have your TDEE, adjusting it determines your outcome. Here is how each goal translates to a practical daily target:

GoalDaily target vs TDEEExpected rateNotes
Maintain weight= TDEEStable weightAllow ±100 kcal tolerance
Slow fat lossTDEE − 250 kcal~0.25 kg/weekEasier to sustain; less muscle loss
Moderate fat lossTDEE − 500 kcal~0.5 kg/weekSweet spot for most people
Aggressive fat lossTDEE − 750 kcal~0.75 kg/weekHigher muscle loss risk; harder to maintain
Lean muscle gainTDEE + 150–250 kcal~0.1–0.2 kg lean/weekSmall surplus; minimises fat gain
Bulk (muscle + some fat)TDEE + 300–500 kcalFaster gain with more fatBest for beginners or underweight individuals

Macronutrient split: where the calories come from

Once you have a daily calorie target, splitting it across protein, carbohydrates and fat determines your energy quality and body composition outcomes. Each macronutrient has a set calorie density:

MacronutrientCalories per gramRecommended range (% of total)Priority note
Protein4 kcal/g25–35%Most important for muscle preservation during fat loss
Carbohydrates4 kcal/g40–55%Primary fuel for exercise and brain function
Fat9 kcal/g20–35%Essential for hormone production; don't go too low
Protein target shortcut: Aim for 1.6–2.2 g of protein per kg of body weight per day when trying to lose fat or build muscle. This is the most evidence-backed single dietary lever for body composition — more reliable than any specific calorie target.

Why the scale doesn't always reflect calorie intake

Several factors cause short-term weight fluctuations that have nothing to do with actual fat gain or loss:

  • Water retention: High-sodium meals or high-carbohydrate days can add 1–2 kg of water weight overnight
  • Gut content: Undigested food in the digestive tract can add 0.5–1.5 kg depending on meal timing
  • Hormonal fluctuations: Can cause multi-day water weight shifts of up to 2 kg in some individuals
  • Muscle glycogen: Starting or increasing carbohydrate intake increases stored glycogen (and associated water), temporarily masking fat loss on the scale

For this reason, tracking a weekly average (sum of 7 days ÷ 7) is far more informative than comparing individual daily weigh-ins. One data point is noise; a two-week trend is a signal.

Common questions

How many calories should I eat per day?

The average sedentary adult needs roughly 1,600–2,000 kcal/day (women) or 2,000–2,500 kcal/day (men) to maintain weight. Your exact number depends on height, weight, age and activity level — a personalised TDEE calculation gives a far more accurate target.

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the calories your body needs at complete rest just to stay alive. TDEE (Total Daily Energy Expenditure) is BMR multiplied by an activity factor to account for movement, exercise and daily living. TDEE is the number you eat at to maintain your current weight.

How large a calorie deficit should I aim for to lose weight?

A deficit of 300–500 kcal per day typically produces 0.3–0.5 kg of fat loss per week — a sustainable rate that preserves most muscle mass. Deficits above 750–1,000 kcal/day significantly increase muscle loss risk and are difficult to sustain, particularly without medical supervision.

Do I need to count calories to manage my weight?

No. Calorie counting is one useful tool, but many people manage weight effectively through food quality, mindful portion sizing, hunger cue awareness and consistent habits. A calorie target is most useful as a reference frame rather than a rigid daily obligation.

Why am I not losing weight despite eating at a deficit?

The most common reasons are: underestimating calorie intake (especially from drinks, oils and sauces), overestimating activity level, water retention masking fat loss on the scale in the short term, or a deficit that is too small to produce measurable weekly loss. Track a weekly average weight over 2–4 weeks before concluding a deficit isn't working.

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