Encore Editorial · Updated 2026-07-02
Estimated daily calorie needs for adults range from about 1,264 calories a day for a sedentary woman age 71 and older to about 3,120 calories a day for a very active or athletic man age 19 to 30, using the Mifflin-St Jeor equation (1990) with a reference adult body size and standard activity multipliers. These figures track the age, sex and activity-level framework used in the USDA/HHS Dietary Guidelines for Americans, 2020-2025. Individual results depend on actual height, weight and body composition, not age and sex alone.
How many calories does an adult need per day?
Daily calorie need is a function of resting metabolism plus activity. Resting metabolism (BMR) is estimated here with the Mifflin-St Jeor equation, published in 1990 and still one of the most validated formulas for the general adult population. Multiplying BMR by an activity factor, from 1.2 for a sedentary day to 1.9 for an athlete in heavy training, gives total daily energy expenditure (TDEE), the estimate of total calories burned. The table below holds height and reference weight fixed within each sex so that age and activity level are the only variables changing from row to row. It is a modeled reference table, not a measurement of any individual, so treat it as a starting point and use the site's calorie deficit calculator or TDEE calculator for a number based on your own height and weight.
Summary table: estimated calories by age, sex, and activity level
| Sex | Age | Sedentary | Moderately active | Very active |
|---|---|---|---|---|
| Men | 19-30 | 1,970 | 2,545 | 2,832 |
| Men | 31-50 | 1,880 | 2,429 | 2,703 |
| Men | 51-70 | 1,760 | 2,274 | 2,531 |
| Men | 71 and up | 1,670 | 2,158 | 2,401 |
| Women | 19-30 | 1,564 | 2,020 | 2,249 |
| Women | 31-50 | 1,474 | 1,904 | 2,119 |
| Women | 51-70 | 1,354 | 1,749 | 1,947 |
| Women | 71 and up | 1,264 | 1,633 | 1,817 |
Figures are calories per day, rounded to the nearest whole number. The full dataset, including "lightly active" and "athlete" columns and the underlying BMR for each row, is in the CSV linked below.
What is the Mifflin-St Jeor equation?
Mifflin-St Jeor is a resting energy expenditure formula published by Mifflin, St Jeor, Hill, Scott, Daugherty and Koh in the American Journal of Clinical Nutrition in 1990. It is the same formula this site's calorie, BMR and TDEE calculators use. In kilograms and centimeters:
| Sex | Formula |
|---|---|
| Men | BMR = 10 × weight (kg) + 6.25 × height (cm) - 5 × age + 5 |
| Women | BMR = 10 × weight (kg) + 6.25 × height (cm) - 5 × age - 161 |
Total daily energy expenditure (TDEE) is BMR multiplied by an activity factor: 1.2 (sedentary), 1.375 (lightly active), 1.55 (moderately active), 1.725 (very active) or 1.9 (athlete). These are the same activity multipliers used across this site's calculators, and they follow the standard activity-factor scale used since the original Harris-Benedict adaptations of the mid-20th century.
Where the reference height and weight come from
Because Mifflin-St Jeor requires a height and weight, not just age and sex, this table fixes one reference body per sex: 5 feet 9 inches at 147 pounds for men, and 5 feet 4 inches at 126 pounds for women. Each reference weight is the midpoint of the healthy BMI range (BMI 21.7) for that height, calculated with this site's own BMI formula. This is the same reference-person approach government calorie tables use to isolate age and activity level as variables. It is not a claim about the average American's actual height or weight. Your own numbers will differ if your height or weight differ from the reference, which is exactly why the table exists alongside a calculator rather than instead of one.
How does this table compare to the Dietary Guidelines for Americans?
The USDA and HHS Dietary Guidelines for Americans, 2020-2025 (9th edition, published December 2020) include their own reference table of estimated calorie needs by age, sex and activity level, built from a different set of equations (the Institute of Medicine's Estimated Energy Requirement formulas) and their own reference weights. Their published adult ranges: men age 19 to 60 need roughly 2,200 to 3,000 calories a day depending on activity level, and women in the same age range need roughly 1,600 to 2,400 calories a day. For adults 61 and older, their ranges run about 2,000 to 2,600 calories for men and 1,600 to 2,000 for women. Those ranges are broadly consistent with the table above, though not identical, because the two tables use different equations and different reference body sizes. Both are estimates, not individual prescriptions.
Methodology
Source formula: Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. "A new predictive equation for resting energy expenditure in healthy individuals." American Journal of Clinical Nutrition. 1990;51(2):241-247. Activity multipliers: standard five-level scale (1.2 to 1.9) used across this site's calorie, BMR and TDEE calculators. Reference body size: a fixed height per sex (5 ft 9 in for men, 5 ft 4 in for women) at the midpoint of the healthy BMI range for that height, calculated with this site's BMI formula. Age groups: midpoint ages of 25, 40, 60 and 75 stand in for the 19-30, 31-50, 51-70 and 71-and-up brackets. Comparison figures: USDA and HHS, Dietary Guidelines for Americans, 2020-2025, 9th edition, December 2020. This page was last updated July 2, 2026, and is scheduled for an annual refresh. It supplements, and does not replace, this site's calorie deficit calculator, which computes a personal number from your actual height, weight, age and activity level.
These figures are estimates for general planning. They are not medical advice. Anyone with a health condition, an eating disorder history, or a significant planned change in diet or activity should consult a doctor or registered dietitian for individual guidance.
Get your personal number
This table uses a fixed reference height and weight. Enter your actual numbers for a result specific to you.