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Calorie Calculator

Find how many calories you burn each day and how much to eat to maintain, lose or gain weight safely.

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Calorie Calculator Nothing is stored or sent

For general information only, not medical advice. Results are estimates and do not replace a check-up with a doctor or other qualified health professional.

What your result means

The calculator gives you several daily calorie targets. “Maintain” is your estimated total daily energy expenditure (TDEE), the calories you burn in a normal day. The other targets add or remove a fixed amount from it.

Goal Daily calories Expected change
Maintain weight TDEE No change
Mild weight loss TDEE − 250 About 0.25 kg (0.5 lb) a week
Weight loss TDEE − 500 About 0.5 kg (1 lb) a week
Extreme weight loss TDEE − 1,000 About 1 kg (2 lb) a week
Mild weight gain TDEE + 250 About 0.25 kg (0.5 lb) a week
Weight gain TDEE + 500 About 0.5 kg (1 lb) a week

Any target below 1,200 kcal a day for women or 1,500 kcal a day for men is flagged as below the safe minimum. These are the lower ends of the weight-loss diets in the 2013 AHA/ACC/TOS obesity guideline (opens in new tab): 1,200 to 1,500 kcal a day for women and 1,500 to 1,800 for men. Eating less makes it hard to get enough protein, vitamins and minerals. The same guideline says very low calorie diets, under 800 kcal a day, belong only under medical supervision.

How calories are calculated

The calculator works in two steps. First it estimates your basal metabolic rate (BMR), the calories your body burns at complete rest. Then it multiplies BMR by an activity factor to get TDEE.

Step 1: BMR with the Mifflin-St Jeor equation

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

Weight and height raise BMR because a bigger body needs more energy. Age lowers it by 5 kcal for every year. The last number adjusts for sex, since men usually carry more muscle.

Step 2: TDEE = BMR × activity factor

  • Sedentary (little or no exercise): × 1.2
  • Lightly active (exercise 1 to 3 days a week): × 1.375
  • Moderately active (exercise 3 to 5 days a week): × 1.55
  • Very active (exercise 6 to 7 days a week): × 1.725
  • Extra active (hard daily exercise or a physical job): × 1.9

The weight change estimates use the common rule that 1 kg of body fat holds about 7,700 kcal (about 3,500 kcal per lb). A 500 kcal daily deficit adds up to 3,500 kcal a week, which is about 0.45 kg, or roughly 0.5 kg. All results are rounded to the nearest whole calorie.

Treat that weekly figure as a first-month guide, not a promise. NIH researchers showed that the body adapts as you lose weight, so the response to a fixed calorie cut slows over time, with a half time of about a year (Hall and colleagues, Lancet 2011 (opens in new tab)).

How to use the calorie calculator

  1. Choose Metric or Imperial, then select your sex and enter your age (18 to 80).
  2. Enter your height and your current weight.
  3. Pick the activity level that matches a typical week, not your best week.
  4. Read your BMR, your maintenance calories and the targets for weight loss or gain. Results update as you type.

Worked example

Priya is a 30-year-old woman. She is 160 cm tall (about 5 ft 3 in), weighs 65 kg (about 143 lb) and exercises 4 days a week, so she picks moderately active.

  1. BMR: 10 × 65 + 6.25 × 160 − 5 × 30 − 161 = 650 + 1,000 − 150 − 161 = 1,339 kcal.
  2. TDEE: 1,339 × 1.55 = 2,075.45, shown as 2,075 kcal. This is her maintenance target.
  3. Mild weight loss: 2,075 − 250 = 1,825 kcal.
  4. Weight loss: 2,075 − 500 = 1,575 kcal, about 0.5 kg a week.
  5. Extreme weight loss: 2,075 − 1,000 = 1,075 kcal. This is below 1,200, so the calculator flags it as below the safe minimum.

For Priya, around 1,575 kcal a day is a sensible starting point. If she wanted to gain weight, the targets would be 2,325 kcal (mild) and 2,575 kcal.

Calorie needs for Indians (ICMR-NIN 2020)

India has its own official numbers. In 2020, the ICMR-National Institute of Nutrition (ICMR-NIN) in Hyderabad revised the daily energy requirement for Indian adults. It works the same way as this calculator: energy need = BMR × physical activity level. The reference man weighs 65 kg and the reference woman 55 kg.

Work type Man, 65 kg Woman, 55 kg
Sedentary work 2,110 kcal 1,660 kcal
Moderate work 2,710 kcal 2,130 kcal
Heavy work 3,470 kcal 2,720 kcal

Source: ICMR-NIN, Nutrient Requirements for Indians 2020 (summary) (opens in new tab). Pregnancy adds 350 kcal a day, and breastfeeding adds 600 kcal in the first six months and 520 kcal after that.

These figures are lower than the 2010 ones, by 210 kcal for a sedentary man and 240 kcal for a sedentary woman. Two reasons are given. Indian studies showed the international FAO/WHO/UNU equations overestimate the BMR of Indians by 10% to 12%, so ICMR-NIN now cuts predicted BMR by 10%. And Indians spend less energy on the same activity, so the multiplier for sedentary work fell from 1.53 to 1.40.

How does that compare with this calculator? For a 30-year-old man of 170 cm and 65 kg, Mifflin-St Jeor gives a BMR of 1,568 kcal. The calculator’s sedentary setting (× 1.2) gives 1,881 kcal and lightly active (× 1.375) gives 2,155 kcal, close to ICMR’s 2,110. For a 30-year-old woman of 155 cm and 55 kg, sedentary gives 1,449 kcal and lightly active 1,661 kcal, almost exactly ICMR’s 1,660. ICMR’s “sedentary” means a desk job plus normal daily chores, so if you walk to work or do housework, lightly active is usually the closer match.

How to lose weight safely

The NHS advises aiming to lose 0.5 kg to 1 kg a week. Slower loss is easier to keep up and more likely to last. A few habits make a calorie target easier to hit:

  • Eat enough protein. Dal, eggs, paneer, curd, fish, chicken and soya keep you full and help protect muscle.
  • Watch portions of rice, roti and oil. In many Indian meals, these are where most of the calories come from. ICMR-NIN advises keeping cooking oil and other visible fat to 20 to 50 g a day, and no more than about 27 g on a 2,000 kcal diet.
  • Drink water, not calories. Sweet tea, juice, soft drinks and alcohol add up fast.
  • Move more. WHO’s 2020 guidelines (opens in new tab) advise adults to get 150 to 300 minutes of moderate activity a week, plus regular muscle-strengthening work.
  • Track for two to three weeks. If your weight does not change, adjust by 100 to 200 kcal rather than cutting hard.

Why weight loss slows down

As you lose weight, your body needs fewer calories. A smaller body burns less at rest and during movement. So the deficit that worked at the start shrinks over time. Re-enter your new weight every few kilos to get updated targets. The BMR calculator shows your resting burn on its own, and the BMI calculator shows your healthy weight range.

If you want to gain weight

The gain targets add 250 or 500 kcal a day. Pair them with strength training 2 to 3 times a week so more of the gain is muscle, not fat. Add calories from nutritious foods such as nuts, milk, curd, eggs, bananas and an extra roti or bowl of dal, rather than sweets and fried snacks. If you are underweight without a clear reason, see a doctor first.

Limitations

All calorie calculators give estimates, not measurements. Real needs can differ from the result by a few hundred calories a day.

  • The formula does not know your body composition. Very muscular people may burn more than shown, and people with obesity may burn less.
  • Activity levels are broad. Most people overestimate how active they are.
  • It is not suitable during pregnancy or breastfeeding, for under-18s, or for people with eating disorders.
  • Thyroid problems, diabetes, PCOS and some medicines can change your energy needs.

See a doctor or registered dietitian before a big change in diet if you have a health condition, take regular medicine, or are aiming to eat below the safe minimum.

Key facts

FAQ

Calorie Calculator FAQs

How many calories should I eat to lose weight?

To lose about 0.5 kg a week, eat roughly 500 calories less than your maintenance calories (TDEE). For a moderately active 30-year-old woman of 160 cm and 65 kg, that is about 1,575 kcal a day. Your number depends on your sex, age, height, weight and activity, so enter your own details in the calculator.

What is TDEE?

TDEE stands for total daily energy expenditure, the total calories you burn in a day. It includes your resting burn (BMR), the energy used to digest food, and all movement, from walking to workouts. The calculator estimates TDEE by multiplying your BMR by an activity factor between 1.2 and 1.9. Eating at your TDEE keeps your weight steady.

How accurate are calorie calculators?

Calorie calculators are a good starting point but can be off by a few hundred calories a day. The Mifflin-St Jeor equation predicts resting burn within 10% of measured for most healthy adults, but activity levels add more error. Track your weight for two to three weeks and adjust by 100 to 200 kcal if it is not moving as expected.

Which activity level should I choose?

Choose the activity level that matches your typical week. If you have a desk job and rarely exercise, pick sedentary. Exercise 1 to 3 days a week is lightly active, and 3 to 5 days is moderately active. Pick very active or extra active only if you train hard almost daily or do heavy physical work. When unsure, choose the lower level.

Is 1,200 calories a day too low?

For many women, 1,200 calories a day is the lowest level usually advised without medical supervision, and for most men the floor is about 1,500. These are the lower ends of the weight-loss diets in the 2013 AHA/ACC/TOS obesity guideline. Going lower makes it hard to get enough nutrients and can cause muscle loss. Diets under 800 kcal need a doctor’s supervision.

How fast can I safely lose weight?

A safe rate for most adults is 0.5 kg to 1 kg (about 1 to 2 lb) a week, as advised by the NHS. That usually means eating 500 to 1,000 calories a day less than you burn. Faster loss often includes water and muscle, is harder to keep up, and raises the risk of gallstones and nutrient gaps.

Should I eat back the calories I burn exercising?

Usually no, if you picked an activity level that already includes your workouts. The activity factor counts your regular exercise, so adding exercise calories again would double count them. Fitness trackers also tend to overestimate calories burned. If you do an unusually long or hard session, eating back a small part of it is reasonable.

How many calories does an Indian adult need per day?

An Indian adult needs about 1,660 to 2,720 kcal a day if a woman and 2,110 to 3,470 kcal if a man, depending on how physical their work is. These ICMR-NIN 2020 figures are for a 55 kg woman and a 65 kg man. A desk job sits at the low end. Your own number depends on your size and age, so use the calculator.