How Many Calories Should I Eat to Lose Weight?
By Jesse · Last updated August 20, 2026
Weight loss comes down to one principle: eat fewer calories than your body burns. That gap is a calorie deficit, and it is the most reliable lever available. The hard part is not the principle, it is picking a number you can hold, knowing what it will actually deliver, and knowing what to change when it stops working.
This guide is about setting the daily target. Two neighbouring questions have their own guides, and this one deliberately does not repeat them: how long the whole process takes is covered in how long weight loss takes, and how much to trust the maintenance figure you start from is covered in why TDEE calculators are estimates.
Step 1: Find your maintenance calories
Before you can eat below maintenance you need to know roughly where maintenance is — the intake that keeps your weight stable. That is your Total Daily Energy Expenditure (TDEE): resting energy plus everything you burn moving. Estimate it with the TDEE calculator. Treat the result as a starting hypothesis with a margin of error around ten percent, not a measurement — Step 5 replaces it with a number derived from your own data.
Step 2: Choose a deficit
A kilogram of body tissue stores roughly 7,700 calories (about 3,500 per pound), so a daily deficit converts into a weekly rate by simple arithmetic. These are the four paces the calorie deficit calculator offers, with what each one implies:
| Loss per week | Daily deficit | To lose 5 kg | To lose 10 kg | Sustainability |
|---|---|---|---|---|
| 0.25 kg (0.6 lb) | 275 kcal | 20 weeks | 40 weeks | Gentle |
| 0.5 kg (1.1 lb) | 550 kcal | 10 weeks | 20 weeks | Moderate |
| 0.75 kg (1.7 lb) | 825 kcal | 7 weeks | 14 weeks | Aggressive |
| 1 kg (2.2 lb) | 1100 kcal | 5 weeks | 10 weeks | Very aggressive |
Computed from the 7,700 kcal per kg model. These are the on-paper figures; the next section explains why real loss runs behind them.
For most people a deficit of 300 to 750 calories per day is the workable band: fast enough to show progress within a month, gentle enough to protect muscle and adherence. Larger deficits are not wrong in principle, they just fail more often in practice, because hunger and fatigue eventually win.
Why every number in that table is the optimistic case
The arithmetic above assumes your maintenance calories stay put. They do not. A lighter body costs less to run, so as you lose weight the gap between your intake and your maintenance narrows on its own — the deficit erodes even though you changed nothing.
Take a concrete plan: woman, 40, 165 cm, 85 kg, moderately active, eating 1,856 kcal against a starting maintenance of 2,356 kcal. That is a clean 500-calorie deficit on day one. Simulating it week by week, recomputing maintenance from the new weight each time:
| Week | Straight-line weight | Simulated weight | Shortfall | Deficit still active |
|---|---|---|---|---|
| Week 12 | 79.5 kg | 79.9 kg | 0.4 kg (7.4% of predicted loss) | 428 kcal (86%) |
| Week 52 | 61.4 kg | 68.2 kg | 6.8 kg (28.8% of predicted loss) | 242 kcal (48%) |
Same body, same fixed intake. The only thing changing is body weight, and therefore maintenance.
By week 52 only 48% of the original deficit is still doing any work, and the straight line has overpromised by 6.8 kg. Left completely alone, this plan converges on about 32.3 kg lost and stops — it reaches half of that in roughly 49 weeks. None of this is metabolic damage or a broken metabolism; it is subtraction. We measured the size of this error across hundreds of plans if you want the general result rather than one example.
The practical consequence is small: expect to re-run the numbers every 8 to 12 weeks, and read any projection beyond about three months as a best case rather than a forecast.
Step 3: Check the target against a floor
Subtracting a large deficit from a small maintenance figure can produce a target nobody should eat. This site clamps calculator output at 1,200 kcal for women and 1,500 kcal for men. Be clear about what those numbers are: planning floors that stop a calculator returning something absurd. They are not clinical safety thresholds, and hitting the floor is not evidence that the target suits you.
Below roughly that level it becomes genuinely difficult to meet protein and micronutrient needs from food, and the risk of losing muscle alongside fat rises. If the arithmetic keeps pushing you under the floor, the answer is usually a smaller deficit held for longer, or more activity rather than less food.
Step 4: Turn the target into food
A calorie number is easier to hit when it is divided up. Protein does the most work in a deficit: it is the most satiating macronutrient per calorie and it is what preserves lean mass while you lose fat, which is why intakes well above the 0.8 g/kg RDA are recommended for people who train. Use the macro calculator to split the target into protein, carbohydrate, and fat, or the protein calculator for the protein figure alone. The protein guide covers where those ranges come from.
Step 5: Replace the estimate with your own data
After two to three weeks of reasonably careful logging you can stop guessing. Your own intake and weight change measure your maintenance directly, which beats any formula because it observes you rather than predicting you. Once you have that figure, put it back into Step 2 in place of the calculator's estimate and reset the target.
The arithmetic, a worked example, and the two ways it misleads are in why TDEE calculators are estimates, which is the guide that owns calibration. There is no point running the same numbers in two places.
When the scale stops moving
"Stalled" covers three different problems with three different fixes. Diagnose before you cut:
- It has not actually stalled. Water, sodium, glycogen, and gut contents move the scale by a kilogram or more in either direction, which is enough to mask two weeks of genuine fat loss. Compare weekly averages, not single readings, before concluding anything.
- Intake has crept up. The most common cause by a wide margin. Portion estimates drift, untracked bites accumulate, and weekends stop resembling weekdays. Re-weigh food for a week before changing the target — you may find the target was never the problem.
- The deficit really has shrunk. The mechanism from earlier: you are lighter, so maintenance is lower. This is the one case where trimming another 100 to 200 calories, or adding activity, is the correct response.
A worked example, start to finish
Maintenance estimated at 2,400 kcal. Pick the moderate pace — a 550 kcal deficit — for a target of 1,850 kcal and a projected 0.5 kg per week, which the table above says reaches 5 kg in 10 weeks. Set protein high, keep the target fixed for three weeks, and log honestly. At the three-week mark, compute actual maintenance from the formula in Step 5 and reset the target from that number instead of the estimate. Then expect the pace to slow, and plan to repeat the exercise every couple of months rather than treating the first number as permanent.
Common questions
How many calories should I eat to lose weight?
Start from your maintenance calories and subtract 300 to 750 per day. A 550 kcal deficit is the usual recommendation for most people, and works out to about 0.5 kg (1.1 lb) per week on paper. The exact target matters less than picking one you can hold for months and then adjusting it from your own weight trend.
Is a 1,200 calorie diet safe?
1,200 is a planning floor, not a clinical safety threshold, and it is the floor this site applies for women (1,500 for men) so a calculator never returns an absurd target. Hitting the floor does not make the target appropriate for you. Very low intakes make it hard to meet protein and micronutrient needs, and are best supervised.
Why has my weight loss stalled when I am still in a deficit?
Three different things get called a stall. Day-to-day water and glycogen shifts can hide two weeks of real fat loss. Intake creep is the most common cause after that, because portion estimates drift upward over time. And a genuine effect: as you get lighter, maintenance falls, so the deficit you set at the start is smaller now. The three have different fixes, so identify which one you have before cutting calories again.
How do I work out my real maintenance calories from my own data?
Take your average daily intake over two to three weeks and your weight change across the same period. Actual maintenance is roughly intake plus (weight change in kg x 7700 / days). If you averaged 2,000 kcal and lost 1 kg over 21 days, maintenance is about 2,000 + (7700 / 21) = 2,367 kcal. This is more accurate than any formula because it measures you rather than predicting you.
Do I need to recalculate my calorie target as I lose weight?
Yes. Maintenance falls by roughly 15.5 kcal per kilogram lost at a moderately active level, so a target set at the start quietly shrinks into a smaller deficit. Re-run the numbers every 5 to 10 kg (10 to 20 lb), or every 8 to 12 weeks, whichever comes first.
Does it matter what I eat, or only how many calories?
Calories decide the direction of weight change; food choice decides how tolerable the deficit is and how much of the loss is fat rather than muscle. Protein is the lever that matters most in a deficit, for both satiety and muscle retention. Beyond that, the best diet composition is the one you can actually adhere to.
These are general estimates for healthy adults, not medical advice. If you are pregnant, under 18, have a medical condition, or a history of disordered eating, talk to a doctor or registered dietitian before cutting calories. See our methodology for the sources behind these figures.