Most adults need somewhere between about 1,600 and 3,000 calories a day. More precisely, the Dietary Guidelines for Americans estimate roughly 1,600 to 2,400 calories a day for women and 2,000 to 3,000 a day for men, with the low end for sedentary people and the high end for active people (Dietary Guidelines for Americans).
That range is wide because your true number is personal. It depends on your age, sex, height, weight, and how much you move, and then on whether you want to maintain, lose, or gain weight. Use the calculator below to get your estimate, then read on to understand what drives the number and how to make it work in real life.
The short answer, by the numbers
The clearest published reference point comes from Appendix 2 of the Dietary Guidelines for Americans, which lists estimated calorie needs to maintain weight for each age and sex group at three activity levels. The headline ranges are simple to remember:
- Adult women: about 1,600 to 2,400 calories a day.
- Adult men: about 2,000 to 3,000 calories a day.
Within each group, the low end is for a sedentary lifestyle and the high end is for an active one (Dietary Guidelines for Americans). These are maintenance figures, the amount that keeps weight stable, and they are estimates built on reference body sizes rather than a measurement of you specifically. They are still the best plain-English starting point before you personalize.
What actually drives your number
Three things decide how many calories you need. Understanding them is what turns a generic range into a number you can trust.
1. Your resting burn (BMR)
Your basal metabolic rate (BMR) is the energy your body spends just staying alive: breathing, pumping blood, repairing cells, keeping your brain on. For most people it is the single largest slice of daily calorie use, often around 60 to 70 percent of the total. Body size and composition push it up or down, which is a big reason a tall, muscular person burns more at rest than a smaller one.
2. Your activity
On top of resting burn, you spend energy moving: workouts, walking, fidgeting, and the everyday motion of living. This is the most variable piece from person to person and the one you have the most control over. Someone with a desk job and no exercise might add only a small fraction to their BMR, while someone training hard most days and on their feet for work can add a great deal.
3. Your goal
Maintenance, the topic of the ranges above, is the baseline. But if you want to change your weight, you deliberately eat above or below that baseline. This is where the same person can have three different “right” numbers: one to maintain, a lower one to lose, and a higher one to gain. We break each down below.
For a fuller walkthrough of how resting burn and activity combine into your total, see BMR vs TDEE: What’s the Difference?.
Estimated daily calories by sex, age, and activity
The table below shows the Dietary Guidelines’ estimated calories to maintain weight for adults, by sex, age, and activity level. Find your row and read across to your activity column for a quick starting estimate (Dietary Guidelines for Americans).
| Sex and age | Sedentary | Moderately active | Active |
|---|---|---|---|
| Women 19–30 | 1,800 – 2,000 | 2,000 – 2,200 | 2,400 |
| Women 31–50 | 1,800 | 2,000 | 2,200 |
| Women 51–60 | 1,600 | 1,800 | 2,200 |
| Women 61+ | 1,600 | 1,800 | 2,000 |
| Men 19–30 | 2,400 – 2,600 | 2,600 – 2,800 | 3,000 |
| Men 31–50 | 2,200 – 2,400 | 2,600 | 2,800 – 3,000 |
| Men 51–60 | 2,200 | 2,400 | 2,600 – 2,800 |
| Men 61+ | 2,000 | 2,200 – 2,400 | 2,400 – 2,600 |
How the activity levels are defined, in the guidelines’ own terms:
- Sedentary: only the physical activity of everyday living.
- Moderately active: everyday living plus the equivalent of walking about 1.5 to 3 miles a day at a brisk pace.
- Active: everyday living plus the equivalent of walking more than 3 miles a day at a brisk pace.
Two patterns stand out. First, needs fall with age: as basal metabolic rate declines, a sedentary woman’s estimate drops from about 2,000 calories in her twenties toward 1,600 by her sixties, and a sedentary man’s from about 2,400 toward 2,000. Second, activity moves the number a lot. Going from sedentary to active can add several hundred calories a day in the same person, which is exactly why two people of the same age and sex can have very different needs.
One caveat: these estimates assume reference body sizes (the guidelines use a reference woman of about 5 feet 4 inches and 126 pounds and a reference man of about 5 feet 10 inches and 154 pounds), and they do not cover pregnancy or breastfeeding, which raise needs. If you are taller, heavier, or built differently than the reference, your number will differ. That is what the personalized calculation in the next section is for.
Calories to maintain, lose, or gain
Once you know roughly what you burn, choosing a target is straightforward. The number you burn in a day is your total daily energy expenditure (TDEE), and it is your maintenance level. From there:
- To maintain weight: eat at your TDEE. Energy in matches energy out, and the scale holds steady.
- To lose weight: eat below your TDEE, usually by about 250 to 500 calories a day. That pace produces a steady loss of roughly 0.25 to 0.5 kg (about 0.5 to 1 lb) a week, which tends to stick better than crash dieting.
- To gain weight: eat above your TDEE, often by about 250 to 500 calories a day, paired with strength training so more of the gain is muscle.
A practical floor is worth keeping in mind: many guidelines advise against dropping below roughly 1,200 calories a day for women or 1,500 for men without medical supervision, because it becomes hard to get enough protein, vitamins, and minerals. For the full method behind the loss target, including safe deficit sizes and why moderate beats aggressive, see How Many Calories Should You Eat to Lose Weight?, and for the science of the gap itself, What Is a Calorie Deficit?.
The size of your deficit also shapes how fast results come and how sustainable they are. If you want to map a target to a realistic timeline, How Much Weight Can You Lose in a Month? lays out what a given deficit translates to on the scale.
How to find YOUR number
The table is a fine starting point, but your own estimate will be tighter. There are two reliable ways to get it.
Use the calculator
The fastest route is the calculator above, or the dedicated calorie calculator and TDEE calculator. You enter your age, sex, height, weight, and activity level, and it returns your estimated maintenance calories plus loss targets. It runs the same math described below, so you do not have to.
Or do the math yourself
Under the hood, well-built calculators use the Mifflin-St Jeor equation, published in 1990 after researchers measured resting energy expenditure in 498 healthy adults, and shown in later comparisons to predict resting needs more accurately than older formulas (Mifflin et al., 1990). First estimate your BMR:
- Women: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) - 161
- Men: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) + 5
Then multiply your BMR by an activity factor to get your TDEE:
| Activity level | What it looks like | Multiplier |
|---|---|---|
| Sedentary | Little or no exercise, desk job | 1.2 |
| Lightly active | Light exercise 1 to 3 days a week | 1.375 |
| Moderately active | Exercise 3 to 5 days a week | 1.55 |
| Very active | Hard exercise 6 to 7 days a week | 1.725 |
| Extra active | Hard daily exercise plus a physical job | 1.9 |
For example, a 35-year-old woman who is 165 cm and 70 kg has a BMR of about 1,370 calories. If she is moderately active, her estimated TDEE is about 1,370 x 1.55, or roughly 2,120 calories a day. That is her maintenance number, the baseline she would eat at to hold steady, cut from to lose, or add to in order to gain.
One honest reminder: this is an estimate, not a lab reading. Prediction equations and activity multipliers are population averages, so your real burn may run a little higher or lower. Use your calculated number as a starting target, then let two to three weeks on the scale tell you whether to nudge it.
Common mistakes to avoid
A few predictable errors throw people’s numbers off. Steering around them keeps your target honest.
- Overrating your activity level. This is the most common one. Picking “very active” when most days are spent sitting inflates your estimate and quietly erases a deficit. When in doubt, choose the lower activity level and let results correct it.
- Forgetting to recalculate. As you lose or gain, your TDEE changes, because a lighter body burns fewer calories and a heavier one more. Recalculate every time your weight shifts by about 4 to 6 kg (roughly 10 lb), or whenever progress stalls for two to three weeks.
- Treating the estimate as exact. No formula nails your burn to the calorie. The number is a hypothesis you test against the scale, not a verdict. Adjust based on the trend, not a single day’s reading.
- Forgetting that liquids and extras count. Drinks, oils, sauces, and “just a bite” add up fast and are easy to leave out. The everyday foods you overlook are usually what separate your real intake from your target.
- Eating too little, too soon. Slashing well below the sensible floors brings hunger, fatigue, muscle loss, and rebound. A moderate target you can keep beats an extreme one you abandon.
Putting it all together
Your daily calorie need comes down to a simple chain: estimate your resting burn, scale it up for activity to get your maintenance number, then aim at, below, or above that depending on your goal. For most adults the answer lands somewhere between about 1,600 and 3,000 calories a day, but the personalized number is the one worth knowing.
Start by running your figures in the calculator above, or build a tailored target with a free plan that turns your number into daily guidance. Then track consistently enough to learn from the feedback: the free CalcEat app lets you snap a photo of your plate for an instant calorie and macro estimate, scan barcodes, or log manually, so you can see whether your intake actually matches your target. Pick your starting number today, give it a couple of weeks, and adjust from there.
This article is general information, not medical advice. If you have a health condition, are pregnant or breastfeeding, or are considering a large change to how you eat, talk with your doctor or a registered dietitian first.
