Most adults need somewhere between 1,600 and 3,000 calories per day to maintain their current weight, depending on their size, age, sex, and how much they move. That range is wide because no single number works for everyone. Your actual maintenance calories depend on your unique metabolism, body composition, and daily habits. The good news: you can get a solid estimate with a simple formula and a few weeks of real-world tracking.
What Maintenance Calories Actually Means
Your body burns energy constantly, even while you sleep. It fuels your heartbeat, breathing, digestion, brain activity, and every fidget and step throughout the day. The total energy you burn in 24 hours is called your total daily energy expenditure, or TDEE. When you eat roughly the same number of calories your body burns, your weight stays stable. That number is your maintenance calories.
TDEE has several components. The largest is your resting metabolic rate (RMR), which accounts for roughly 60 to 70 percent of your daily burn and covers the energy needed just to keep you alive. The thermic effect of food, meaning the energy your body uses to digest and absorb what you eat, adds another 10 percent or so. The rest comes from physical activity, both structured exercise and all the smaller movements you make throughout the day.
How to Estimate Your Number
The most reliable formula for estimating resting metabolic rate is the Mifflin-St Jeor equation. A systematic review in the Journal of the American Dietetic Association found it predicted resting metabolism within 10 percent of measured values in more people than any other commonly used equation, across both normal-weight and obese adults.
Here’s how it works:
- For men: (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) + 5
- For women: (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161
That gives you your resting metabolic rate in calories. To get your full daily burn, multiply by an activity factor:
- Sedentary (desk job, little to no exercise): multiply by 1.2
- Lightly active (light exercise 1 to 3 days per week): multiply by 1.375
- Very active (intense exercise 6 to 7 days per week): multiply by 1.725
For example, a 35-year-old woman who weighs 150 pounds (68 kg), stands 5’5″ (165 cm), and exercises a few times a week would calculate: (10 × 68) + (6.25 × 165) − (5 × 35) − 161 = roughly 1,396 calories at rest. Multiply by 1.375 for light activity, and her estimated maintenance is about 1,920 calories per day. A 35-year-old man with the same height and weight would land around 2,160 calories at the same activity level.
Why Formulas Are Only a Starting Point
Even the best equation is an estimate. The Mifflin-St Jeor formula has a margin of error, and its accuracy can vary across age groups and ethnic backgrounds. More importantly, the activity multiplier is a rough guess. Two people who both “exercise three times a week” might have wildly different daily movement patterns outside the gym.
This is where non-exercise activity thermogenesis, or NEAT, comes in. NEAT includes every calorie you burn through fidgeting, walking to the kitchen, standing while cooking, pacing during phone calls, and even maintaining your posture. According to research from the Mayo Clinic, NEAT can vary by up to 2,000 calories per day between two people of similar size. That’s an enormous gap, and it explains why some people seem to eat more without gaining weight. They simply move more in small, unconscious ways throughout the day.
Fitness trackers can help you get a sense of your daily movement, but don’t trust their calorie estimates at face value. Studies have found calorie-burn estimates from wearable devices range from 27 to 93 percent error. Even the most accurate devices tested still overestimated by about 27 percent. Walking and running estimates tend to be more reliable (around 31 percent error) than cycling (52 percent error). Use your tracker for step counts and activity trends rather than precise calorie numbers.
The Real-World Way to Find Your Number
The most accurate method combines a formula estimate with actual tracking. Start by eating the calorie amount the Mifflin-St Jeor equation suggests. Weigh yourself at the same time each day, first thing in the morning, for two to three weeks. Daily weight fluctuates due to water, sodium, and digestion, so look at the weekly average rather than any single day.
If your average weight stays stable over two to three weeks, you’ve found your maintenance range. If you’re slowly gaining, reduce by 100 to 200 calories and observe for another two weeks. If you’re slowly losing, add the same amount. This trial-and-error process is more reliable than any calculator because it accounts for your actual metabolism, your real activity level, and all the individual quirks no equation can capture.
How Body Composition Affects Your Burn
Muscle tissue is more metabolically active than fat tissue. Each pound of muscle burns roughly 5 to 7 calories per day at rest, while fat burns considerably less. That difference sounds small per pound, but it adds up. Someone carrying 20 extra pounds of muscle compared to someone of the same weight with more fat could burn 100 to 140 additional calories daily just by existing.
This is one reason two people who weigh the same, stand the same height, and share the same age can have noticeably different maintenance calories. It’s also why strength training matters for long-term weight maintenance. Preserving or building muscle keeps your resting metabolism from dropping as you age.
Your Maintenance Calories Will Change Over Time
The number of calories that keeps your weight stable today won’t necessarily work five years from now. Several factors shift your maintenance calories over time.
Age is the most predictable one. Resting metabolism declines gradually as you get older, partly because of natural muscle loss and partly because of hormonal changes. By your 50s and 60s, you may need 200 to 300 fewer calories than you did at 30 to maintain the same weight.
Weight loss itself can temporarily change the equation. After losing a significant amount of weight, your body burns somewhat fewer calories than a formula would predict for your new size. Research in the American Journal of Clinical Nutrition found this dip averages about 50 calories per day. However, the same study found that this metabolic slowdown largely disappears within one to two years of maintaining the new weight. In other words, your metabolism adjusts downward after a diet, but it typically recalibrates once you’ve been weight-stable for a while.
Changes in your job, daily routine, or exercise habits also matter. Switching from a job where you’re on your feet to a desk job can easily cut 300 to 500 calories from your daily burn. Seasonal changes in activity level, injuries that limit movement, or simply getting a car after years of walking to work can all shift the balance.
What to Eat at Maintenance
Hitting the right calorie target matters, but so does what fills those calories. Protein plays a particularly important role in weight maintenance. The bare minimum recommended intake is 0.36 grams per pound of body weight, but that’s a floor to prevent deficiency, not an optimal target. Most nutrition researchers suggest higher intakes for maintaining muscle mass, typically in the range of 0.5 to 0.8 grams per pound. For a 160-pound person, that’s 80 to 128 grams of protein per day.
Protein also has a higher thermic effect than carbohydrates or fat, meaning your body uses more energy to digest it. This doesn’t dramatically change your calorie math, but it does contribute to feeling full and preserving lean tissue, both of which make maintaining your weight easier over time. Beyond protein, filling your calories with a mix of whole grains, fruits, vegetables, and healthy fats gives your body the micronutrients it needs and tends to keep hunger more manageable than ultra-processed alternatives at the same calorie count.
Quick Reference Ranges
If you want a ballpark before running any formulas, these general ranges cover most adults:
- Sedentary women: 1,600 to 2,000 calories per day
- Active women: 2,000 to 2,400 calories per day
- Sedentary men: 2,000 to 2,400 calories per day
- Active men: 2,400 to 3,000 calories per day
These ranges assume adults between roughly 25 and 50 years old. Younger adults and taller individuals trend toward the higher end. Older adults and smaller individuals trend lower. Use these as a sanity check, then dial in your personal number using the formula and tracking method above.