How many calories should I eat to lose weight?

There is no single number of calories that applies to everyone. How many calories you should eat to lose weight depends on your current weight, your height, your age and how much you move, and any answer that ignores those is a guess dressed up as advice. A calorie calculator can only help once it knows those four things about you.

Start from what you burn, not from a round number

The figures people repeat, 1,200 for women and 2,000 or 2,500 for men, are population averages rather than a target derived from anything about you. Your own number starts from what your body needs in a day.

The NHS suggests eating fewer calories than you burn by around 600 kcal a day, which it describes as a healthy and sustainable way to lose weight^{[NHS Better Health]}. As a general reference its dietary guidelines put average daily calories at roughly 2,000 for women and 2,500 for men, but those are not your calorie needs, and treating them as a goal is where most weight loss efforts go wrong.

Working out the calories needed to maintain your current weight

Two steps. Estimate your basal metabolic rate (BMR), the energy your body burns at rest^{[American Journal of Clinical Nutrition]}. Then multiply by a factor for your physical activity. The result is your total daily energy expenditure, usually shortened to TDEE, and it is the number of calories that would maintain your current weight.

The BMR calculator does the first step. The TDEE calculator does both, which saves running a calorie calculator by hand and getting the multiplier wrong.

What that looks like with real numbers

Take a woman of 40, 5 ft 5 in, 13 stone, who walks a bit and sits down for work. Her resting energy is about 1,500 calories. Multiplied for that activity, the daily calories that maintain her current weight come to roughly 2,060, and taking 600 off gives a daily calorie intake near 1,460.

Change one answer and the arithmetic moves. As sedentary rather than lightly active, her maintenance drops to about 1,800, putting the same daily calorie deficit just under 1,200 calories per day. That is well below what her body needs at rest, and this site will not recommend it: the calculator raises the figure and says so. Same person, same method, 260 calories apart on one dropdown.

The calorie deficit is the part that matters

A daily calorie target is not interesting on its own. What produces weight loss is the calorie deficit, the gap between the calories you burn and the calories you eat. Run a deficit and the body makes up the excess energy from its fat stores.

Two people can safely lose weight at the same rate while eating 1,400 and 2,300 calories, because they are not the same size and do not burn the same number of calories. Comparing your calorie intake with somebody else's tells you nothing about your own weight loss journey. Our calorie deficit calculator works the gap out from your figures, and the weight loss calculator turns it into a timeframe and a healthy weight range.

A deficit of 500 to 550 calories per day is roughly a pound a week. Around 1,100 a day would be two pounds a week, which is rapid weight loss, more than most people hold and more than the NHS suggests^[NHS].

Why 1,200 calories is usually the wrong answer

1,200 calories is below the resting calorie needs of a great many adult women, before any movement. Very low calorie diets make it hard to get enough protein, calcium, iron and other essential vitamins, they are difficult to sustain, and nutrient deficiencies become a real risk alongside losing more muscle mass than fat.

No calorie calculator here will suggest an intake below your estimated resting needs. If your pace would push it that low, the minimum calorie calculator shows where your floor sits. Eating too many calories is not the only way weight management goes wrong; eating far too few is the other, and it is worth raising with a health professional rather than pushing through.

Protein, and what a smaller day has to carry

Weight lost is rarely purely fat. The larger the deficit, the greater the share that tends to come from lean tissue rather than fat, and protein intake is the part of a healthy balanced diet most associated with limiting that. Resistance training helps too: lifting weights while in a deficit is associated with holding on to more lean tissue than dieting alone. The protein calculator gives a target for your body weight and the share of your calories it takes up.

Beyond protein, a balanced diet matters for reasons unrelated to weight. Calorie counting says nothing about nutrition. Healthy meals built from whole foods and the same number of calories from heavily processed foods will not leave you feeling the same, even if the arithmetic is identical.

Physical activity changes the multiplier, not the subtraction

Regular exercise raises the figure you subtract from rather than adding a second subtraction. Treating a workout as licence to eat extra calories on top is how people end up under their resting needs without meaning to.

Calorie burn from exercise also moves the number less than expected. An hour of brisk walking is perhaps 250 calories for many adults. The honest use of physical activity is that it lets you eat more calories while still losing weight.

When the number and the scales disagree

Two things go wrong far more often than a broken metabolism. The first is the activity multiplier, set one level too high. The second is hidden calories: olive oil in a pan, milk in several coffees, the part of the packet never weighed.

Liquid calories are the easiest to miss, because they do not feel like eating. Fizzy drinks, fruit juices and sugary drinks all count in full, while sugar free drinks, black coffee, water and lemon juice cost almost nothing. Neither miss is a moral failing and both are measurable.

Weighing portion sizes for a week, keeping a food diary, reading nutrition labels or using a calorie tracking app is usually enough to find the gap. Not as a permanent habit, but as a measurement. Small, repeatable healthy habits beat a perfect week followed by weight gain.

Recalculate as you go

As you lose weight you need fewer calories, so the deficit you set at the start shrinks. Healthy choices hold better when the target is current, so recalculate every four to six weeks. The plateau calculator shows how much of your original deficit is left at your new weight, and the maintenance calorie calculator gives the daily calories that hold a healthy weight once you arrive. The BMI calculator and the ideal weight calculator show where that range sits for your height.