Published on October 19, 2026 · Our editorial process
Ask ten people how many calories you should eat a day and you will hear “2,000” ten times. That number comes from the back of a food label, and it is a rounded average for a country of 330 million people. Your own number depends on your sex, your age, your size, and how much you move, and it can sit anywhere from 1,600 to 3,000 without anything being wrong.
This guide gives you the official ranges by age and sex, shows you how to find your own number in two minutes, explains how to adjust it for losing or gaining weight, and covers the situations where the usual rules do not apply.
Key takeaways
- Most adult women need 1,600 to 2,400 calories a day and most adult men 2,000 to 3,000, according to the Dietary Guidelines for Americans. Where you land depends mostly on age and activity.
- To find your own number, work out your maintenance calories, the amount that keeps your weight steady. A calculator does it in seconds, or you can use the simple formula below.
- To lose weight, eat 250 to 500 calories below maintenance, which gives about half a pound to a pound a week. Do not go under 1,200 calories a day as a woman or 1,500 as a man without medical advice.
- Pregnancy, breastfeeding, the teenage years, and heavy training all raise calorie needs. Age lowers them.
How many calories should you eat a day? The official ranges
The Dietary Guidelines for Americans publish estimated calorie needs by age, sex, and activity level. The figures below are for adults of average height and healthy weight. “Sedentary” means only the activity of normal daily life. “Moderately active” means the equivalent of walking 1.5 to 3 miles a day at a brisk pace on top of that. “Active” means more than 3 miles a day of brisk walking or the equivalent.
| Age | Sedentary | Moderately active | Active |
|---|---|---|---|
| Women | |||
| 19 to 30 | 1,800 to 2,000 | 2,000 to 2,200 | 2,400 |
| 31 to 50 | 1,800 | 2,000 | 2,200 |
| 51 and over | 1,600 | 1,800 | 2,000 to 2,200 |
| Men | |||
| 19 to 30 | 2,400 to 2,600 | 2,600 to 2,800 | 3,000 |
| 31 to 50 | 2,200 to 2,400 | 2,400 to 2,600 | 2,800 to 3,000 |
| 51 and over | 2,000 to 2,200 | 2,200 to 2,400 | 2,400 to 2,800 |
The UK figures are simpler. The NHS gives a guide of about 2,000 calories a day for women and 2,500 for men, which sits in the middle of the American ranges. Both are averages. A 5-foot-2 woman who works at a desk and a 5-foot-10 woman who runs most days both fall under “women 31 to 50,” and their needs can differ by 600 calories.
How to find your own number
The ranges above are a starting point. Your own figure is your maintenance calories, sometimes called your TDEE, which is the number of calories you burn in a typical day. Eat that much and your weight stays the same. There are two ways to get it.
The quick way
Use our TDEE and maintenance calorie calculator. Enter your sex, age, height, weight, and activity level and it gives your maintenance calories plus the targets for losing or gaining weight. It takes about a minute.
The by-hand way
The calculator uses the Mifflin-St Jeor equation, which research has found to be the most accurate general formula. You can run it yourself:
- Multiply your weight in kilograms by 10. To get kilograms, divide pounds by 2.2.
- Add 6.25 times your height in centimeters. To get centimeters, multiply inches by 2.54.
- Subtract 5 times your age.
- Add 5 if you are a man, or subtract 161 if you are a woman. This is your resting metabolism, the calories you burn doing nothing.
- Multiply by an activity factor: 1.2 if you are sedentary, 1.375 if lightly active, 1.55 if moderately active, 1.725 if very active, 1.9 if you train hard every day or have a physical job.
Example: a 40-year-old woman, 5 feet 5 inches, 160 pounds, who walks most days and does a workout twice a week. Weight 72.7 kg times 10 is 727. Height 165 cm times 6.25 is 1,031. Minus 200 for age, minus 161 for being female, gives a resting metabolism of 1,397. Times 1.375 for lightly active gives about 1,920 calories a day to maintain her weight.
Be honest about activity
This is where most people go wrong. Three gym sessions a week with a desk job and a car is “lightly active,” not “moderately active.” If you are unsure, pick the lower level. Starting low and adjusting up after two or three weeks is less frustrating than starting high and wondering why the scale is not moving.
How many calories to eat to lose weight
Eat below your maintenance number, but not far below. A deficit of 500 calories a day gives roughly one pound of loss a week, which is the pace the NHS and most health bodies recommend. A deficit of 250 gives about half a pound a week, which is slower but far easier to keep up, and it protects more muscle.
Using the example above, the woman maintaining on 1,920 calories would aim for about 1,420 to lose a pound a week, or 1,670 to lose half a pound. Both are comfortable. Trying to lose two pounds a week would put her at 920, which is below the floor most dietitians use.
That floor matters. Below about 1,200 calories a day for women and 1,500 for men, it becomes very hard to get enough protein, iron, calcium, and other nutrients, energy drops, and the body starts to burn muscle. If a sensible deficit takes you under those numbers, lose weight more slowly or add movement instead of cutting food further. And recalculate every 10 pounds, because a lighter body burns fewer calories and the deficit shrinks as you go.
How many calories to eat to gain weight or muscle
Eat above maintenance, but only a little. A surplus of 250 to 500 calories a day supports muscle growth when it is paired with strength training two or three times a week and enough protein, around 0.7 grams per pound of body weight. Go much higher than that and the extra mostly becomes fat. Underweight people trying to regain weight can use the same range, prioritizing calorie-dense but nutritious foods such as nuts, nut butters, olive oil, full-fat dairy, and oats.
Calories for children and teenagers
Children need fewer calories than adults but far more per pound, because they are growing. The Dietary Guidelines ranges, from sedentary to active, are roughly 1,000 to 1,400 calories for ages 2 to 3, 1,200 to 2,000 for ages 4 to 8, and 1,400 to 2,600 for ages 9 to 13. Teenagers often need more than their parents: 1,800 to 2,400 for girls aged 14 to 18 and 2,000 to 3,200 for boys the same age, with active teenage boys at the top of that range. Children should not count calories or be put on deficits without a doctor or dietitian involved. The job of a parent is to offer regular, balanced meals and let appetite do the counting.
When the usual numbers do not apply
- Pregnancy. No extra calories are needed in the first trimester. The second trimester adds about 340 calories a day and the third about 450. That is a sandwich and a glass of milk, not eating for two.
- Breastfeeding adds roughly 330 to 400 calories a day for the first six months.
- Over 65. Needs fall as muscle is lost and activity drops, but protein needs stay the same or rise. Older adults who cut calories without keeping protein up lose strength fast.
- Heavy training. Endurance athletes and people with physical jobs can need 3,500 calories or more. The activity factors above cover this, but if you are losing weight you do not want to lose, eat more.
- Illness and recovery. Surgery, infection, and burns raise needs. Follow the advice of the team treating you.
- Thyroid conditions and some medicines shift metabolism. If your weight changes in a way the calculator cannot explain, see a doctor rather than cutting further.
What the calories should be made of
Hitting the right number with the wrong food leaves you hungry, tired, and short on nutrients. A simple pattern that works at any calorie level: protein at every meal, which keeps you full and protects muscle; vegetables and fruit for volume and fiber; whole grains and beans for steady energy; and fats from olive oil, nuts, seeds, and fish. Breakfast is where a lot of people lose the day, either skipping it or starting with sugar. A bowl of oats with fruit and nuts is one of the cheapest fixes there is, and our guide to what happens when you eat oatmeal every day explains why it keeps you full until lunch.
Liquid calories are the other trap. A large sweetened coffee or two sodas can be 400 calories that do nothing for hunger. Swapping those alone is often enough to create the deficit without changing a single meal.
How accurate is any of this?
Honestly, within about 10 percent for most people. The formula lands close to measured metabolism for roughly seven out of ten adults, and the activity factor adds some guesswork on top. Food labels are allowed to be off by up to 20 percent, and most people underestimate what they eat by a good margin. The way to make the number accurate is feedback: weigh yourself a few mornings a week, average each week, and compare. If the weekly average is flat on your calculated maintenance calories, the number is right. If you are gaining, your real figure is lower, so take 150 off. If you are losing, add some back. After a month you will know your own number better than any formula.
When to talk to a doctor
Talk to a doctor or registered dietitian before changing your calories if you have diabetes, kidney disease, heart disease, or a history of disordered eating, if you are pregnant or breastfeeding, or if you take medicines that affect appetite or blood sugar. See a doctor if you are losing weight without trying, if you cannot lose weight on a sensible deficit after two months, or if dieting leaves you dizzy, exhausted, or constantly cold.
The bottom line
Most women need 1,600 to 2,400 calories a day and most men 2,000 to 3,000, but the useful number is your own maintenance figure, which the calculator or the formula gives you in a minute. Eat that to stay the same, 250 to 500 less to lose weight at a sensible pace, or 250 to 500 more to gain. Stay above the safety floors, recalculate as your weight changes, and let two or three weeks of weigh-ins fine-tune the number. Then spend your attention on what the calories are made of, which matters at least as much as how many there are.
Frequently asked questions
How many calories should a woman eat a day?
Most adult women need 1,600 to 2,400 calories a day to maintain their weight, with about 2,000 as a common average. Younger, taller, and more active women sit at the top of the range, and women over 50 or with desk jobs at the bottom. To lose weight, eat 250 to 500 calories below your own maintenance figure, but not under 1,200 a day without medical advice.
How many calories should a man eat a day?
Most adult men need 2,000 to 3,000 calories a day, with about 2,500 as an average. Active men under 30 can need 3,000 or more, and sedentary men over 50 closer to 2,000. For weight loss, eat 250 to 500 below maintenance, and not under 1,500 a day without medical supervision.
How many calories should I eat to lose weight?
Work out your maintenance calories, then subtract 500 for about a pound a week or 250 for about half a pound a week. For many women that lands between 1,400 and 1,800 calories, and for many men between 1,800 and 2,300. Stay above 1,200 calories for women and 1,500 for men, and recalculate every 10 pounds.
Is 1,200 calories a day enough?
For most adults, no, not as a long-term intake. It is the lowest level most dietitians consider safe for women without supervision, and it is hard to meet protein and nutrient needs on it. Smaller, older, sedentary women may maintain their weight on 1,400 to 1,600, but 1,200 should be a short-term floor, not a target.
Is 1,500 calories a day enough?
For many women it is a reasonable weight-loss intake, giving a deficit of 300 to 700 calories below a typical maintenance level. For most men it is too low except as a short-term plan under supervision, since it sits at the safety floor. Whether it is right for you depends on your own maintenance figure.
How many calories should I eat by age?
Calorie needs peak in the late teens and twenties and fall by roughly 50 to 100 calories a day per decade after that, as muscle declines and activity drops. A moderately active woman needs about 2,000 to 2,200 at 25 and about 1,800 at 55. A moderately active man needs about 2,600 to 2,800 at 25 and about 2,200 to 2,400 at 55.
Do I need to eat back the calories I burn exercising?
If you chose an activity level that already includes your workouts, no, because they are already counted. Adding the calories your watch reports on top would count them twice. If you did an unusually long session, eating back about half of it is a sensible middle ground.
How do I know if I am eating the right amount?
Track your weight a few mornings a week and average it weekly. A flat weekly average means you are at maintenance. A steady drop of half a pound to a pound a week means a healthy deficit. If you are losing faster than that, feeling weak, cold, or dizzy, or constantly hungry, you are eating too little.
