Calorie Tracking
How Many Calories Should I Eat Per Day to Lose Weight
How many calories you should eat per day to lose weight. Calculate your TDEE, set a deficit, and find the sweet spot for sustainable fat loss.
The honest answer to "how many calories should I eat to lose weight" is: fewer than you burn, by an amount you can keep up for months. Everything below turns that into a number for you. It explains the three steps, works through four real examples, and shows when to adjust.
If you just want your number, the free calorie calculator does all of this in about 30 seconds, and the calorie deficit calculator compares every weekly pace side by side. Read on to understand where the number comes from and how far to trust it.
Step 1: Estimate what you burn (your TDEE)
Your total daily energy expenditure (TDEE) is the calories your body uses in a full day. It has three parts:
- Basal metabolic rate (BMR): the energy you use at complete rest, usually 60–70% of the total.
- Thermic effect of food: the energy used to digest and store what you eat, roughly 10% of intake.
- Activity: workouts plus everything else you do on your feet, from walking to the car to fidgeting. This is the part that varies most between people.
You can't measure TDEE at home, but you can estimate it well. First calculate BMR with the Mifflin-St Jeor equation, which a systematic review found to be the most reliable of the common equations for healthy adults. Then multiply BMR by an activity factor. The step-by-step method is in our guides on how to calculate BMR and how to calculate TDEE.
Step 2: Choose how fast to lose
A kilogram of body fat stores roughly 7,700 kcal (about 3,500 kcal per pound). So an average daily deficit of 550 kcal adds up to about 0.5 kg (1.1 lb) a week at the start. The calculator on this site uses that same conversion:
| Weekly goal | Daily deficit | Monthly loss (early on) |
|---|---|---|
| Lose 0.25 kg (0.5 lb) | about 275 kcal | about 1 kg (2.2 lb) |
| Lose 0.5 kg (1 lb) | about 550 kcal | about 2 kg (4.4 lb) |
| Lose 0.75 kg (1.5 lb) | about 825 kcal | about 3 kg (6.6 lb) |
Two rules of thumb help you choose:
- Keep the deficit around 10–25% of TDEE. Bigger deficits make hunger, low energy and muscle loss more likely, and most people abandon them sooner.
- Aim for roughly 0.5–1% of body weight per week. Evidence reviews for lean, trained people recommend this range, and a study in elite athletes found that slower loss (about 0.7% a week) preserved more lean mass than faster loss (about 1.4% a week). If you have more weight to lose, the upper end is usually fine. If you are already fairly lean, stay near the lower end.
Step 3: Subtract, then check the floor
Daily calorie target = TDEE − daily deficit.
Then check the result against a floor. Many clinical weight-loss programmes don't go below about 1,200 kcal a day for women or 1,500 kcal a day for men without medical supervision. Below that, it becomes hard to get enough protein, fibre and micronutrients. The calculator on this site never sets a target below 1,200 kcal. If your maths lands under the floor, choose a slower weekly goal or add activity instead of cutting food further.
Worked examples
All four examples use Mifflin-St Jeor and standard activity factors, the same maths as the calculator.
| Person | BMR | Activity | TDEE | Lose 0.25 kg/wk | Lose 0.5 kg/wk | Lose 0.75 kg/wk |
|---|---|---|---|---|---|---|
| Woman, 35, 165 cm, 75 kg | 1,445 | Light (×1.375) | 1,987 | 1,712 | 1,437 | 1,200 (floor) |
| Man, 40, 180 cm, 90 kg | 1,830 | Light (×1.375) | 2,516 | 2,241 | 1,966 | 1,691 |
| Woman, 28, 160 cm, 58 kg | 1,279 | Sedentary (×1.2) | 1,535 | 1,260 | 1,200 (floor) | 1,200 (floor) |
| Man, 30, 178 cm, 80 kg | 1,768 | Moderate (×1.55) | 2,740 | 2,465 | 2,190 | 1,915 |
What the table shows:
- The same weekly goal is a much bigger ask for smaller, less active people. For the 35-year-old woman, 0.5 kg a week means a 550 kcal deficit, about 28% of her TDEE. That's above the comfortable range, so 0.25–0.4 kg a week (a deficit of about 275–450 kcal) is the more sustainable choice.
- For the 28-year-old woman, anything faster than 0.25 kg a week hits the floor. Walking more (moving from sedentary to lightly active adds about 225 kcal of burn) is a better lever than eating less.
- Active people have more room. The 30-year-old man can eat 2,190 kcal and still lose 0.5 kg a week, because his training raises his TDEE.
Why the number is a starting point, not a verdict
Equations predict the average person with your age, height, weight and sex. You may burn more or less than that. In the original Mifflin-St Jeor research and the reviews that followed, most people's measured resting burn fell within about 10% of the prediction, but some were further off. Activity estimates add more uncertainty, because people often misjudge their own activity level.
So treat your target as a hypothesis and test it:
- Eat at your target consistently for 2–3 weeks and log what you eat.
- Weigh yourself several times a week under the same conditions (for example after waking, before eating) and compare weekly averages, not single days.
- Compare the actual rate of loss with the one you planned. Each 0.1 kg per week of difference is roughly 110 kcal a day. If you planned 0.5 kg a week but the average only moved 0.3 kg, eat about 220 kcal less, or move more.
Water shifts from salt, carbohydrate, hormones and training soreness can hide fat loss for a week or two. Adjust based on trends of three weeks or more, not a single weigh-in.
Your number will change as you lose weight
A smaller body burns less. If the 35-year-old woman above goes from 75 kg to 65 kg, her BMR drops by about 100 kcal and her TDEE at the same activity level by about 137 kcal. A target that produced steady loss at the start produces slower loss later. On top of that, the body adapts to a deficit by moving a little less and becoming slightly more efficient.
This is also why simple "3,500 kcal = 1 lb" projections overestimate long-term loss. A mathematical model published in The Lancet by NIH researchers estimates that each lasting change of about 24 kcal a day (100 kJ) eventually shifts body weight by about 1 kg, or roughly 10 kcal a day per pound. About half of that change happens in the first year and nearly all of it within three years. The NIH Body Weight Planner, built on that model, gives more realistic long-range forecasts.
In practice: recalculate your target after every 4–5 kg (about 10 lb) of loss, or whenever your weekly average stalls for three weeks or more.
Make the target easier to hit
The number only works if you can eat at it most days. The things that make that easier are well supported:
- Prioritise protein. Diets higher in protein (about 1.2–1.6 g per kg of body weight) improve fullness and help preserve muscle during weight loss. See how much protein you need per day.
- Keep strength training. It tells your body to hold on to muscle while you lose fat.
- Watch liquid and restaurant calories. They are the easiest to underestimate. Our guides on low calorie drinks and tracking calories when eating out cover the common traps.
- Log honestly for a few weeks. You don't have to track forever, but a few weeks of accurate logging will calibrate your eye for portions.
FAQ
Is 1,200 calories a day enough to lose weight?
For many smaller or less active women, 1,200 kcal a day creates a deficit. For most men and active women it is an unnecessarily large deficit that is hard to sustain and makes muscle loss more likely. Use it as a floor, not a default.
Should I eat back the calories I burn exercising?
If you chose your activity level to include your workouts, no: they are already in your TDEE. If you picked "sedentary" and track workouts separately, eat back part of them (about half is a common approach), because trackers often overestimate calories burned.
How many calories should I eat to lose 1 kg a week?
About 1,100 kcal a day below your TDEE. That is a large deficit for most people. It is only realistic if your TDEE is well above 2,500 kcal, and even then 0.5–0.75 kg a week is easier to sustain and better for keeping muscle.
Why am I not losing weight in a calorie deficit?
Usually one of three things: intake is higher than logged (cooking oils, drinks, weekends), activity is lower than the level you chose, or water retention is masking fat loss. Check a three-week weight trend and a week of careful logging before you cut further.
Do I need a different number on rest days?
Not necessarily. A weekly average matters more than any single day. Some people like to eat a bit more on training days and a bit less on rest days, but the result is the same if the weekly total matches.
This guide is general information for healthy adults. If you are pregnant or breastfeeding, under 18, managing a medical condition, or have a history of disordered eating, get advice from a doctor or registered dietitian before you set a calorie deficit.
Sources
- Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990.
- Frankenfield D, Roth-Yousey L, Compher C. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. J Am Diet Assoc. 2005.
- Hall KD, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011.
- National Institute of Diabetes and Digestive and Kidney Diseases. Body Weight Planner.
- Thomas DM, et al. Can a weight loss of one pound a week be achieved with a 3500-kcal deficit? Int J Obes. 2013.
- Garthe I, et al. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab. 2011.
- Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr. 2014.
- Leidy HJ, et al. The role of protein in weight loss and maintenance. Am J Clin Nutr. 2015.