Calorie needs at age 21, female
TDEE is the number of calories you burn in a day. This page works it out for a 21-year-old woman at 5 ft 4 in and 150 lb, then shows how it changes with activity.
How it works
Resting calories are 10 times weight in kilograms plus 6.25 times height in centimeters minus 5 times age. Add 5 for males or subtract 161 for females. Multiply by 1.2 for little exercise up to 1.9 for very hard training. Here the woman aged 21 has a height of 162.56 cm and a weight of 68.04 kg, at the lightly active level.
Worked example
A woman aged 21 is 162.56 cm tall and weighs 68.04 kg. Multiply weight by 10: 10 × 68.04 = 680.4. Multiply height by 6.25: 6.25 × 162.56 = 1016. Subtract 5 × 21 = 105. Subtract 161. The total is 1430.4, or 1430 calories at rest. Multiply 1430.4 by 1.375 for the lightly active level. That gives 1966.8, or 1967 calories a day.
Maintenance calories at every activity level for the same woman aged 21 at 5 ft 4 in and 150 lb, with the lightly active level set in the form above.
- Sedentary (little or no exercise)
- 1716 calories a day
- Lightly active (light exercise 1 to 3 days a week)
- 1967 calories a day
- Moderately active (moderate exercise 3 to 5 days a week)
- 2217 calories a day
- Very active (hard exercise 6 to 7 days a week)
- 2467 calories a day
- Extra active (very hard exercise and a physical job)
- 2718 calories a day
Common questions
What is the difference between BMR and TDEE?
BMR is what your body burns at rest. TDEE adds the calories you use moving and exercising. It is always higher. For this woman aged 21 at 150 lb, BMR is 1430 calories and TDEE at the lightly active level is 1967.
Which activity level should I pick?
Pick the one that matches a typical week, not your best week. If you sit most of the day and train a few times, lightly or moderately active is usually closer than very active. Across the five levels this 21-year-old woman ranges from 1716 to 2718 calories a day, and the lightly active level gives 1967.
How big a calorie deficit is reasonable for weight loss?
A deficit of 500 calories a day is a common starting point and works out to roughly half a kilogram a week. Smaller deficits are slower and easier to keep up. A 500 calorie deficit here means 1467 calories a day for this 21-year-old woman at the lightly active level.
How big a surplus helps build muscle?
A modest surplus of about 250 calories a day is a common starting point. Larger surpluses tend to add more fat without adding muscle faster. A 250 calorie surplus here means 2217 calories a day for this 21-year-old woman at the lightly active level.
Why does age 21 change the result?
The formula takes 5 calories off for every year of age, which reflects that resting burn tends to fall over time. At 21 that is 105 calories. Without the age term this 21-year-old woman would burn 1535 calories at rest, or 2111 a day at the lightly active level.