Daily Calorie Needs Calculator
Enter your sex, age, height, weight and lifestyle to estimate the energy you need in a day to keep your weight: your basal metabolic rate multiplied by a physical activity level (PAL) from the FAO/WHO/UNU report.
- Low end of the category (PAL 1.40)1,918 kcal/day
- High end of the category (PAL 1.69)2,316 kcal/day
- Basal metabolic rate (BMR)1,370 kcal/day
How it is calculated
Your daily energy need is the energy you need in a day to keep your weight. The report of the 2001 FAO, WHO and United Nations University expert consultation defines it for adults as basal metabolic rate times physical activity level (PAL) and groups lifestyles into three PAL categories. In a sedentary or light lifestyle the job takes little physical effort, travel is mostly by vehicle and there is no regular exercise. A desk worker who does about an hour of moderate to vigorous exercise every day, such as jogging, cycling or aerobic dancing, raises PAL, in the report’s words, “from 1.55 (corresponding to the sedentary category) to 1.75 (the moderately active category)”; masons and construction workers are other examples of the moderate level. A vigorous lifestyle means several hours of strenuous work or exercise every day. The report says the PAL adults can sustain over a long period is about 1.40–2.40, and higher values are hard to keep up for long. In the report PAL multiplies a BMR from FAO’s own equations (Table 5.2, Schofield 1985); this tool applies the same PAL values to a BMR estimated with the equations of the BMR calculator (Mifflin–St Jeor by default).
Daily energy need = BMR × PALBMR: basal metabolic rate (kcal/day), by default with the Mifflin–St Jeor equation: 10 × weight + 6.25 × height − 5 × age + 5 (men) / − 161 (women). PAL: physical activity level, total energy expenditure over 24 hours divided by BMR. FAO/WHO/UNU categories: sedentary or lightly active 1.40–1.69, active or moderately active 1.70–1.99, vigorously active 2.00–2.40.- Work out your basal metabolic rate with the chosen equation (Mifflin–St Jeor, Harris–Benedict, or Katch–McArdle with your body fat).
- Choose your lifestyle category. The tool uses the category’s mid-point: 1.55, 1.85 or 2.20. Only 1.85 is printed in the report as a “mid-point” (p. 40); 1.55 is the average the report gives as “corresponding to the sedentary category” (p. 39; the arithmetic mid-point is 1.545), and 2.20 is calculated as the arithmetic mid-point of the range, not printed in the report.
- Multiply BMR by PAL and round to whole calories; the values at the low and high end of the category are shown too.
- If you know your own PAL (for example from a measured total expenditure), enter it with “My own PAL value”.
Example
A 30-year-old woman, 165 cm, 65 kg, sedentary or lightly active: BMR = 10 × 65 + 6.25 × 165 − 5 × 30 − 161 = 1,370.25 kcal/day. Daily need = 1,370.25 × 1.55 = 2,123.89 ≈ 2,124 kcal/day; 1,918 at the low end of the category (1.40) and 2,316 at the high end (1.69).
Frequently asked questions
How do I choose my activity level?
Think of your typical day over the last month or longer, not a single day. If you mostly sit at work, travel by vehicle and do no regular sport, you are sedentary or lightly active. If you do about an hour of moderate to vigorous exercise every day, or your job is physical, you are moderately active. If you do several hours of strenuous work or exercise every day, you are vigorously active.
Why aren’t the 1.2–1.9 multipliers used on other sites here?
The common 1.2 / 1.375 / 1.55 / 1.725 / 1.9 multipliers are not FAO/WHO/UNU values, and we could not verify where they come from. This tool uses the FAO/WHO/UNU PAL categories, whose ranges and definitions are published. If you know your own PAL, you can enter it with “My own PAL value”.
How accurate is the result?
It is an estimate. The FAO/WHO/UNU report says the requirement varies by about ±8–10% around each category’s mid-point and that its figures are meant for population groups, not individuals; a person’s need can only come from their measured expenditure or an estimate that takes their lifestyle into account. The BMR equations carry their own error too.
How much less should I eat to lose weight?
This tool estimates the energy you need to keep your weight; it does not set a weight target. By Hall’s (2008) model, the common “3,500 kcal deficit per pound” rule roughly holds only for obese people with more than 30 kg of body fat and overestimates the deficit needed for people with less fat. Hall and colleagues (2011) showed that body weight responds slowly to a change in energy intake (a half-time of about one year). Before setting a target, talk to your doctor or a dietitian; the US NIDDK’s Body Weight Planner gives a plan over time.
Can I use it when pregnant, breastfeeding or under 18?
No. The report defines BMR × PAL as the daily requirement for adult men and for adult women who are not pregnant or breastfeeding; pregnancy, breastfeeding and growth need extra energy. In these cases, ask your doctor or a dietitian.
Source
- FAO/WHO/UNU. Human energy requirements: Report of a Joint FAO/WHO/UNU Expert Consultation, Rome, 17–24 October 2001. FAO Food and Nutrition Technical Report Series 1, Rome 2004: Table 5.3 and section 5.3 (p. 38, PAL categories, sustainable range), section 5.3.2 (p. 39, lifestyle examples, 1.55 → 1.75), section 5.4.1 (p. 40, category mid-point 1.85, ±8–10%, for population groups; BMR from the Table 5.2 equation), Table 5.2 (BMR equations, Schofield 1985), section 2.6 (p. 9, PAL definition)
- Mifflin MD, St Jeor ST et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 1990;51(2):241–7, abstract (default BMR equation)
- Harris JA, Benedict FG. A biometric study of human basal metabolism. PNAS 1918;4(12):370–3, p. 373 (equations for men and women)
- Cunningham JJ. Body composition as a determinant of energy expenditure. Am J Clin Nutr 1991;54(6):963–9, abstract (Katch–McArdle: 370 + 21.6 × fat-free mass)
- Hall KD. What is the required energy deficit per unit weight loss? Int J Obes 2008;32(3):573–6, abstract (the 3,500 kcal rule roughly holds only for obese people with over 30 kg of body fat)
- Hall KD, Sacks G, Chandramohan D et al. Quantification of the effect of energy imbalance on bodyweight. Lancet 2011;378(9793):826–37, abstract (half-time of about one year)
- NIDDK (US National Institutes of Health), Body Weight Planner