Calorie Calculator: TDEE, BMR and Your Daily Target

How many calories do I need a day?

It depends on your size, age, sex and how much you move. Your BMR, the energy your body burns at rest, comes from the Mifflin-St Jeor equation. Multiplied by an activity factor it gives your TDEE, the calories you burn in a whole day.

Eat about your TDEE to stay at your weight, 500 kcal a day less to lose about 0.5 kg a week, or 300 to 500 kcal more to gain. A 35-year-old woman of 160 cm and 62 kg who is lightly active burns about 1,766 kcal a day.

The BMR uses the equations in Mifflin and St Jeor's 1990 paper and the TDEE the five activity multipliers that a 2022 BMC Nutrition study applies to them. The dishes are one default portion each from HPB's Singapore Food Insights Database.

All checked 7 November 2026. It is an estimate for healthy adults, not medical advice, so if you are pregnant, under 18 or managing a medical condition, ask your doctor or a dietitian for your number.

What is the difference between TDEE and BMR?

BMR is what you burn lying still for a day, and TDEE is what you burn living it. Mifflin and St Jeor measured the resting energy use of 498 healthy adults aged 19 to 78, about half of them obese, and fitted this equation to it: 10 x weight in kg + 6.25 x height in cm - 5 x age in years, then + 5 for men or - 161 for women.

TDEE adds everything else, from walking to the MRT to a training session, by multiplying the BMR by a factor for how active you are.

So BMR changes only as your weight and age change, while TDEE moves with your week. Your calorie target comes from TDEE, never from BMR alone.

How do you work out your calories by hand?

Work out your BMR, multiply it by your activity factor, then add or take away for your goal. Here it is for a 35-year-old woman, 160 cm tall and 62 kg, who does light exercise 1 to 3 days a week.

A man of the same age, height and weight would have a BMR 166 kcal higher, the gap between + 5 and - 161, and a TDEE about 228 kcal higher at the same activity.

Which activity level should you pick?

The one that matches an ordinary week, not your best one. Most people with a desk job who train two or three times a week are lightly active. If you sit between two levels, start with the lower one, then weigh yourself for two to three weeks and adjust. The table shows how much the choice moves the worked example.

The gap from the bottom row to the top is 899 kcal a day. Picking a level too high is an easy way to overestimate what you can eat.

How big a calorie deficit is safe for weight loss?

About 500 kcal a day for most adults. Singapore's HPB-MOH clinical practice guidelines on obesity recommend diets with a deficit of at least 500 kcal below estimated daily needs, and say loss should preferably not exceed 0.5 to 1 kg a week.

HealthHub gives the same 0.5 to 1 kg ceiling. Writing for SingHealth's HealthXchange, Dr Tham Kwang Wei of Singapore General Hospital puts a 500 kcal daily cut at about 0.5 kg a week.

Bigger is not better. The same SGH article says eating under 1,000 to 1,200 kcal a day may be counterproductive, so this calculator never shows a loss target under 1,200 kcal. If 500 kcal under your TDEE would go below that, it stops at 1,200 and tells you the loss will be slower.

Diets of about 800 kcal a day or less are what the US National Institute of Diabetes and Digestive and Kidney Diseases calls very low-calorie diets, run under a health professional's supervision. If the scale is not moving on your number, the usual causes are in why am I not losing weight.

What does your calorie target look like in hawker food?

For the worked example's 1,266 kcal, a plate of steamed chicken rice is 38% of the day and a plate of char kway teow 77%. The figures are each dish's default portion in HPB's SG FoodID database, which replaced its older food composition database. Portions at your stall will differ, so treat them as a guide.

Chicken rice for lunch and sliced fish beehoon soup for dinner come to 929 kcal, which leaves 337 kcal for breakfast, drinks and snacks. Swap the soup for char kway teow and the two meals alone are 1,449 kcal, over the day's target. Ordering tips stall by stall are in the hawker eating guide for fat loss.

Why is the number only an estimate?

Because the equation predicts the average person of your size, not you. In the 1990 study, weight, height, age and sex explained 71% of the differences in measured resting energy use between people, so two people with the same inputs can burn noticeably different amounts. The activity multipliers are a convention on top of that, and you cannot know which level fits until you see what your weight does.

Your needs also fall as you lose weight. The HPB-MOH guidelines note that every 24 kcal a day you cut eventually means about 1 kg less body weight, so a steady 500 kcal cut levels off about 21 kg lighter rather than carrying on at 0.5 kg a week.

Use the number as a starting point: hold it for two to three weeks, weigh yourself on the same mornings, and recalculate after every few kilos.

Where does a personal trainer fit in?

The calories decide how much weight you lose, and the training decides how much of it is fat rather than muscle. Fit Titans matches you with a freelance coach who trains you at home, in your condo gym, at a park or at a Gym Pod. Our coaches build the strength sessions and keep you consistent.

They are not dietitians, so a medical diet belongs with a dietitian. How coached fat loss works is on our weight loss page, training without a gym is in how to lose weight without a gym, and the protein side is in how much protein you need.