Calorie Calculator – How Many Calories Should You Eat Per Day?

Start with the basics: your age, current body weight (pounds or kilograms depending on which unit you pick), and your height. These go directly into the BMR formula, so accuracy matters more than you might think. Using last year's weight or rounding your height by a couple inches can throw off the result more than expected.

Then you'll select your activity level from the available options. A lot of people pause here, which is why there's a more detailed breakdown in the next section.

Most people underestimate how active they are. Some go the other direction. Here's a quick way to think through it:

• Sedentary: Desk job, minimal walking, no structured exercise.
• Lightly active: Light exercise one to three days per week, or a job that keeps you on your feet part of the day.
• Moderately active: Moderate exercise three to five days per week. Most consistent gym-goers fall somewhere in this range.
• Very active: Hard training six or seven days a week, or a physically demanding job on top of regular workouts.
• Extremely active: Two-a-day training, physical labor combined with regular exercise, or similar high-output situations.

When in doubt, go one level lower than you think. It's much easier to eat a bit more if you're losing weight too fast than to cut back after things stall out.

Once you hit calculate, you'll see your Total Daily Energy Expenditure, or TDEE. That's the estimated number of calories your body burns on an average day given your current stats and activity level. Think of it as your maintenance number, the point where calories in roughly equals calories out.

From there, the calculator usually shows adjusted targets for weight loss, weight gain, or maintenance. Those are based on a standard calorie deficit or surplus, which is covered in more detail further down the page. The number you get is an estimate, not a guarantee, but it's a solid, research-backed place to start.

Your Basal Metabolic Rate (BMR) is the number of calories your body burns doing absolutely nothing. Breathing, keeping your heart going, regulating temperature, all the background processes that never stop. For most people, this accounts for roughly 60 to 70 percent of total daily calorie burn.

The Mifflin-St Jeor equation is generally considered the most accurate BMR formula for the general population, outperforming older methods like the Harris-Benedict equation in multiple validation studies. It uses your weight, height, and age to produce a calorie estimate specific to your body.

BMR alone doesn't tell you what you need to eat. You also burn calories through movement, whether that's a gym session, a walk to the mailbox, or just fidgeting at your desk. To account for all of that, your BMR gets multiplied by an activity factor.

The result is your TDEE, Total Daily Energy Expenditure. This is the number that actually matters when setting a calorie goal. A sedentary person's TDEE might be only 20 percent above their BMR. A competitive athlete's could be nearly double it.

The Mifflin-St Jeor equation differs slightly for men and women to account for average differences in lean muscle mass and body composition. Both versions use weight in kilograms, height in centimeters, and age in years.

If you're working in pounds and inches, convert first: divide pounds by 2.205 to get kilograms, and multiply inches by 2.54 to get centimeters.

Find the row that best matches your lifestyle and multiply your BMR by that number. That's your TDEE.

These are general benchmarks, not personal prescriptions. Pregnancy and breastfeeding both significantly increase calorie needs and aren't captured in this table. Talk to a healthcare provider for guidance during those periods.

Men generally need more calories than women of the same age mainly because of greater average muscle mass and body size. Your personal TDEE from the calculator will be more accurate than these broad averages for most people.

To lose weight, you need to eat fewer calories than you burn. That gap is called a calorie deficit. A daily deficit of 500 calories is the most commonly recommended starting point, and it works out to roughly one pound of fat loss per week on paper.

Bigger deficits can speed things up, but they come with tradeoffs: more muscle loss, increased hunger, lower energy, and it's just harder to stick to. Most nutrition professionals suggest keeping the deficit somewhere between 500 and 750 calories per day for steady, sustainable results. Going beyond 1,000 calories under maintenance isn't generally recommended unless you have medical supervision.

A practical rule of thumb: don't eat less than 80 percent of your TDEE while dieting, and never drop below the minimum safe thresholds covered at the bottom of this page.

Gaining weight, specifically lean muscle, means eating more than you burn. But more isn't always better. A modest surplus of 250 to 500 calories per day is usually enough to support muscle growth while keeping unnecessary fat gain in check.

Eating 1,000 or more calories above maintenance (sometimes called a "dirty bulk") does move the scale faster, but a good chunk of that gain tends to be fat you'll need to cut later. For most people who aren't on a strict timeline, a lean bulk in the 250 to 500 calorie range produces cleaner results over time.

Maintenance is pretty much what it sounds like: eating roughly the same number of calories you burn so your weight stays stable. Your TDEE is that number.

Worth keeping in mind though: maintenance isn't a fixed target you calculate once and never revisit. Your TDEE shifts as your weight changes, as you age, and as your activity level goes up or down. Lose 20 pounds and your maintenance calories drop too. Recalculating every few months, or whenever something in your life changes noticeably, keeps your targets from drifting too far off.

The idea that 3,500 calories equals one pound of fat has been around since the 1950s and still gets used widely because it's a reasonable approximation for practical planning. One pound of body fat stores roughly 3,500 calories of energy, so a 500-calorie daily deficit over seven days gets you to that number.

That said, it's a simplification. Real weight loss isn't perfectly linear. Hormonal responses, water retention, changes in activity, and metabolic adaptation all cause your actual results to diverge from the math, especially over longer stretches of time. Treat the 3,500-calorie rule as a planning guide rather than a precise prediction, and adjust based on what the scale actually shows over two to four weeks.

For most healthy adults, losing between 0.5 and 2 pounds per week is considered a safe and sustainable range. Aiming for the lower end, around half a pound to one pound per week, tends to preserve more muscle and is a lot easier to keep up over time.

If you're consistently losing more than two pounds a week without being on a medically supervised program, it's worth taking a second look at your deficit. Aggressive calorie restriction tends to backfire: metabolism slows down, hunger hormones ramp up, and most people end up dropping the plan well before they reach their goal.