Is BMI accurate for everyone?

BMI is a quick screening tool, not a diagnosis. It does not distinguish muscle from fat, so very muscular people may read as overweight. It is also less precise across some ethnic groups — use it as a guide alongside other measures.

What is the difference between BMR and TDEE?

BMR is the energy your body burns at complete rest. TDEE adds the calories you burn through daily activity and exercise — it is the number to aim for if you want to maintain your current weight.

How do I lose or gain weight from my TDEE?

Eating roughly 300–500 kcal below your TDEE supports gradual weight loss; eating above it supports weight gain. Sustainable changes beat extreme deficits.

BMI calculator with BMR & calories

BMI, healthy weight range, BMR, and daily calorie needs.

Calculate your Body Mass Index (BMI) and see which category you fall into under Malaysia's national clinical guideline, the healthy weight range for your height, your Basal Metabolic Rate (BMR), and the daily calories you need to maintain your weight (TDEE). Malaysia uses lower BMI thresholds than the international chart, so the answer here may differ from other calculators.

How the BMI calculator works

BMI is your weight in kilograms divided by your height in metres squared. Malaysia's Clinical Practice Guidelines for the Management of Obesity (2nd edition, 2023), issued by the Ministry of Health with the Malaysian Endocrine and Metabolic Society, set pre-obesity at a BMI of 23 and obesity above 27.5.

Those thresholds are lower than the international 25 and 30 because the international chart was drawn from a Caucasian reference population. Asians — including Malaysia's Malay, Chinese and Indian populations — carry more body fat at the same BMI and develop diabetes and cardiovascular disease at lower values, so the risk begins earlier. The calculator applies the Malaysian figures and tells you when the international chart would have said something different.

BMR is estimated with the Mifflin-St Jeor equation, which uses your weight, height, age, and sex. TDEE then multiplies BMR by an activity factor from 1.2 (sedentary) to 1.9 (very active).

The healthy weight range is the weight that would put your BMI between 18.5 and 23 at your current height — the upper bound is the Malaysian pre-obesity cut-off, not the international one.

BMI categories apply to adults only. For anyone under 18 the guideline directs that the WHO BMI-for-age chart be used instead, because a healthy BMI changes with a child's age and sex. The calculator shows the BMI figure for a child but withholds the category rather than applying an adult threshold that does not fit.

Formulas used

BMI = weight(kg) ÷ height(m)²

BMR (male) = 10·kg + 6.25·cm − 5·age + 5

BMR (female) = 10·kg + 6.25·cm − 5·age − 161

TDEE = BMR × activity factor

BMI categories for Malaysian adults (MOH CPG 2023)

Applies to adults aged 18 and over. Under-18s should be assessed with the WHO BMI-for-age chart.

BMI	Category	International chart would say
Below 18.5	Underweight	Underweight
18.5 – 22.9	Normal weight	Normal weight
23.0 – 27.5	Pre-obese (overweight)	Normal up to 25, then overweight
Above 27.5	Obese	Overweight until 30, then obese

Frequently asked questions

Is BMI accurate for everyone?: BMI is a quick screening tool, not a diagnosis. It does not distinguish muscle from fat, so very muscular people may read as overweight. It is also less precise across some ethnic groups — use it as a guide alongside other measures.
What is the difference between BMR and TDEE?: BMR is the energy your body burns at complete rest. TDEE adds the calories you burn through daily activity and exercise — it is the number to aim for if you want to maintain your current weight.
How do I lose or gain weight from my TDEE?: Eating roughly 300–500 kcal below your TDEE supports gradual weight loss; eating above it supports weight gain. Sustainable changes beat extreme deficits.