How Many Calories to Lose Weight (Full Guide)

To lose weight, eat about 500 calories per day below your maintenance level (TDEE), which produces roughly 1 pound of fat loss per week. For most adults that lands somewhere between 1,200 and 2,000 calories a day, but the exact number depends on your body size, age, sex, and activity. Find your maintenance calories, subtract a sensible deficit, and hold that average over time.

Key takeaways

• A 500-calorie daily deficit targets about 1 pound of weight loss per week; a 250-calorie deficit targets about half a pound.
• Your target = maintenance calories (TDEE) minus your chosen deficit. Estimate TDEE from your weight, height, age, sex, and activity, then subtract.
• The “3,500 calories = 1 pound” figure is a useful planning estimate, not a precise law — actual loss slows over time as metabolism adapts.
• Common safe-minimum guidance is about 1,200 calories/day for women and 1,500 calories/day for men; going lower usually requires medical supervision.
• Your weekly average intake and your long-term weight trend matter far more than any single day.

How many calories to lose weight per week?

Weight loss comes down to eating fewer calories than you burn. The size of that gap — your calorie deficit — sets how fast you lose. A widely used estimate holds that a pound of stored body fat represents roughly 3,500 calories, so a deficit of about 3,500 calories across a week corresponds to about a pound of loss.

Here’s how that math translates into daily targets:

The Dietary Guidelines for Americans and the CDC both point to a gradual pace — around 1 to 2 pounds per week — as the range most people lose and keep off. Faster isn’t better here. Aggressive deficits are harder to stick to and cost you more muscle, which is exactly what you don’t want to lose.

What is TDEE, and how do I find my maintenance calories?

Your Total Daily Energy Expenditure (TDEE) is the number of calories you burn in a day — your maintenance level. Eat that amount and your weight holds steady. It’s built from a few parts:

• BMR (basal metabolic rate) — the calories your body burns at rest just to stay alive. It’s the biggest chunk, and it’s estimated from your weight, height, age, and sex, usually with the Mifflin-St Jeor equation.
• Activity — everything on top of resting: walking, workouts, fidgeting, and the energy used to digest food. This is applied as a multiplier from about 1.2 (sedentary) up to 1.9 (very active).

So TDEE = BMR × activity multiplier. You don’t have to do the arithmetic by hand — our free calorie and TDEE calculator returns your maintenance number and a weight-loss target in a few seconds. Once you know the calories, our guide to tracking macros covers how to split them into protein, carbs, and fat.

One caveat: activity multipliers and BMR formulas are estimates. Two people the same size can differ by a few hundred calories. Treat your calculated TDEE as a starting point, then let the scale correct it (see the last step below).

How do I calculate my calorie deficit?

Three steps, no complicated math:

1. Get your maintenance calories. Say the calculator puts your TDEE at 2,200 calories.
2. Choose a deficit from the table above. Pick 500 for the standard ~1 lb/week.
3. Subtract. 2,200 − 500 = 1,700 calories per day. That’s your target.

That’s the whole formula: daily target = maintenance − deficit. Everything else — protein, food choices, timing — is about making that number stick.

How many calories should I eat a day?

There’s no single answer, because a 5’2” sedentary person and a 6’2” active person have very different maintenance levels. In practice, most adults eat somewhere between 1,200 and 2,000 calories a day while losing weight. The reliable way to personalize it is to calculate your own TDEE and subtract a deficit, rather than copy a number from someone whose body isn’t yours.

What’s a safe minimum number of calories?

Cutting deeper doesn’t speed things up in a way worth having. Very low intakes drive more muscle loss, more hunger, and worse adherence — you burn out and rebound.

As a general floor, most adults shouldn’t drop below about 1,200 calories per day (women) or 1,500 calories per day (men) without a doctor’s oversight. Very-low-calorie diets — typically defined as around 800 calories a day or fewer — are a real medical tool for some people, but the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) is clear that they should be done only under medical supervision, not improvised at home.

The takeaway: a moderate deficit you can hold for months beats a punishing one you abandon in a week.

Why does the 3,500-calorie rule overstate weight loss?

You’ll see “3,500 calories equals a pound” everywhere, and it’s genuinely useful for planning. But it’s a simplification, not physics.

As you lose weight, you become a smaller body that burns fewer calories — so your maintenance level drops and the same food intake produces a smaller deficit over time. This is metabolic adaptation, and it’s normal. It’s why loss almost always slows the longer you diet, and why a target that worked in month one may stall by month three.

The NIH built this into the NIDDK Body Weight Planner, a research-based tool that models how your energy needs change as you lose weight rather than assuming a flat 3,500-per-pound rule. The practical lesson is simple: expect the slowdown, and re-check your target every few weeks instead of assuming the first number holds forever.

Why am I not losing weight in a calorie deficit?

Nine times out of ten, the “deficit” is smaller than it looks on paper. The usual culprits:

• Untracked calories. Cooking oils, dressings, drinks, and bites while cooking add up fast. A tablespoon of olive oil is about 120 calories; a couple of them can erase your entire deficit.
• Portion creep. Eyeballed portions drift larger over time. Weighing food for a week resets your calibration.
• Overestimated activity. Fitness trackers and machines tend to inflate calories burned, which makes your real maintenance lower than assumed.
• Water weight masking fat loss. Sodium, carbs, stress, and hormones can hold water for days, hiding real fat loss on the scale. This is why you judge progress by a 2 to 4 week trend, not a single morning.

Tighten your tracking first, give it a few weeks, and only then lower your target by 100 to 200 calories if the trend is genuinely flat.

Do protein and consistency really matter that much?

Yes. Two habits do most of the heavy lifting inside a deficit:

• Enough protein. Protein preserves muscle while you lose fat and keeps you fuller on fewer calories. A common range is 1.6 to 2.2 grams per kilogram of body weight. Our macro tracker breaks every meal into protein, carbs, and fat so hitting that number isn’t guesswork — and how to track macros covers the full setup.
• Consistency. Your average intake across weeks is what changes your body. One high day won’t undo a good week; a good week won’t survive a chaotic month. Aim for a target you can hit most days, not a perfect day you can hit rarely.

How to actually hit your target without burning out

The math is the easy part. The reason most people fail isn’t the arithmetic — it’s the daily friction of logging every meal. Manual entry is exactly what wears people down.

A photo-based tracker removes that friction: snap your plate, and LensNutra’s AI food scanner logs the calories and macros against your goal so you always see how much you have left for the day. Pair it with a smoothed weight progress tracker, which averages your daily weigh-ins into a trend line so a single water-weight spike doesn’t derail you. When the trend flattens, that’s your signal to adjust — the same last step in the process above.

The bottom line

Find your maintenance calories, subtract about 500 for roughly a pound a week, keep protein high, and stay consistent. Re-check the number every few weeks against your real weight trend, and hold a deficit you can actually live with. Do that, and steady weight loss follows.

Calculate your calorie target now, then download LensNutra to track it without the busywork.