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Health · Calorie & energy needs

Calorie calculator(TDEE)

Your TDEE (Total Daily Energy Expenditure) is the number of calories your body burns in a day — the figure you need to know before losing or gaining weight. It starts from your BMR (Basal Metabolic Rate, the energy you'd burn at complete rest) and scales it up by how active you are. Enter your details to see your BMR, your maintenance calories, and exactly how many calories to eat to hit a weight goal, plus a suggested split of protein, carbs and fat.

About you

Sex
Calculation method

Keep Standard — it suits almost everyone. Choose Body-fat % only if you know your body-fat percentage; it's the most accurate then. (Standard = Mifflin-St Jeor, Classic = Harris-Benedict, Body-fat % = Katch-McArdle.)

Macro split

Your daily energy needs

BMR

1618

kcal

Calories burned at complete rest

Maintenance (TDEE)

2507

kcal

Calories to stay at your current weight

Activity factor

×1.55

BMR → Maintenance (TDEE)

Calorie targets by goal

How many calories to eat each day, and the weight change that implies (about 7,700 kcal per kilo of body fat).

GoalCalories/dayWeekly change

* Capped at your BMR — eating below your resting needs for long isn't recommended.

Your macros

A suggested split of your selected goal's calories into protein, carbohydrate and fat.

Carbs

313

g · 50%

Protein

125

g · 20%

Fat

84

g · 30%

2507 kcal per day

Estimate for educational use only — not medical or dietary advice. Calorie equations are population averages and your real needs can vary by 10–15%. Speak to a doctor or dietitian before starting a restrictive diet.

How it's calculated

First we estimate your BMR — the calories you'd burn doing nothing all day. The default Mifflin-St Jeor equation for a man is 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5; for a woman the last term is −161. A 30-year-old man, 80 kg and 180 cm, has a BMR of about 1,780 kcal.

Then we multiply BMR by an activity factor (1.2 sedentary up to 1.9 extra active) to get your TDEE — the calories you actually burn in a day. At 'moderately active' (×1.55), that 1,780 BMR becomes 2,759 kcal of maintenance. To lose weight you eat below it; to gain, above it.

Why it matters

Weight change is ultimately about energy balance: eat less than your TDEE and you lose, eat more and you gain. Knowing your number turns vague dieting into a plan — a 500 kcal daily deficit works out to roughly half a kilo a week. It matters in Malaysia especially: the 2023 National Health and Morbidity Survey found 54.4% of adults are overweight or obese, and portion-heavy local favourites like nasi lemak and teh tarik make it easy to drift past your maintenance calories without noticing.

Man, 30, 80 kg, 180 cm, moderately active

Worked example

Using the Mifflin-St Jeor equation and a 1.55 activity factor:

BMR = 10 × 80 + 6.25 × 180 − 5 × 30 + 5 = 1,780 kcal/day.

TDEE = 1,780 × 1.55 = 2,759 kcal/day (maintenance).

To lose weight, eat 2,259 kcal (a 500 kcal deficit) → about −0.45 kg/week.

To gain, eat 3,259 kcal (a 500 kcal surplus) → about +0.45 kg/week.

Common mistakes

Where calorie maths trips people up:

  1. 01Overstating your activity level

    Most people pick a level too high. A gym session 3 times a week with a desk job is 'lightly' to 'moderately' active, not 'very active'. Overestimating inflates your TDEE and stalls weight loss.

  2. 02Cutting calories too hard

    Eating far below your BMR backfires — energy crashes, muscle loss, and a metabolism that adapts down. A 500 kcal deficit is sustainable; a 1,000 kcal one rarely is for long.

  3. 03Treating the number as exact

    These are population-average equations. Your true burn can differ by 10–15%. Use the figure as a starting point, then adjust based on how your weight actually moves over 2–3 weeks.

Frequently asked questions

7 answers
What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the calories your body burns at complete rest just to stay alive. TDEE (Total Daily Energy Expenditure) is BMR multiplied by an activity factor — the calories you actually burn in a full day including movement and exercise. TDEE is the number you use to plan your diet.

How many calories should I eat to lose weight?

Eat below your TDEE. A 500 kcal daily deficit gives roughly half a kilo of fat loss per week, which is a safe, sustainable pace. The calculator shows your exact targets — but it won't drop you below your BMR, since eating under your resting needs long-term isn't recommended.

Which BMR formula is most accurate?

Mifflin-St Jeor (1990) is the modern default and the most accurate for the general population, so it's selected here by default. Katch-McArdle is more accurate if you know your body-fat percentage, because it works from lean body mass. Harris-Benedict is the classic older formula and tends to read slightly high.

What activity level should I choose?

Be honest and lean conservative. Sedentary is a desk job with little exercise; lightly active is light workouts 1–3 days a week; moderately active is 3–5 days; very active is hard training 6–7 days; extra active adds a physically demanding job. Most office workers who exercise a few times a week are lightly to moderately active.

How does the weekly weight change work?

One kilogram of body fat stores about 7,700 kcal. So a 500 kcal daily deficit is 3,500 kcal a week, which is roughly 0.45 kg of fat — that's why the calculator shows −0.45 kg/week rather than a round half-kilo. The same maths applies to weight gain on a surplus.

What are macros and which split should I pick?

Macros are the three energy nutrients: protein, carbohydrate and fat. The calculator splits your calories using a preset — Balanced (50% carbs / 20% protein / 30% fat), Low carb, or High protein. Higher protein helps preserve muscle when losing weight. The splits are illustrative starting points, not prescriptions.

Is this calculator suitable for everyone?

It's built for healthy non-pregnant adults. It can misjudge needs for athletes with high muscle mass, the elderly, pregnant or breastfeeding women, and people with medical conditions affecting metabolism. Treat it as an educational estimate and consult a doctor or dietitian before any restrictive diet.

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