Calorie Calculator

The Calorie Calculator can be used to estimate the number of calories a person needs to consume each day. This calculator can also provide some simple guidelines for gaining or losing weight.

Your Details

Your Results

Fill in your details and click Calculate to see your calorie needs

— kcal Recommended daily intake

— kcal TDEE (maintenance calories)

— kcal BMR • —

How these numbers are calculated

BMR = calories burned at complete rest
→ Default: Mifflin–St Jeor
→ With Body Fat %: Katch–McArdle (more accurate)
TDEE = BMR × Activity multiplier
Target = TDEE adjusted for goal
→ Fat loss: –350 to –800 kcal
→ Muscle gain: +250 to +450 kcal
→ Maintenance: = TDEE

Estimates only (±10–20%). Track weight 2–3 weeks and adjust ±100–200 kcal.

Health Implications of Body Mass Index

This Calorie Calculator is based on several equations, and the results of the calculator are based on an estimated average. The Harris-Benedict Equation was one of the earliest equations used to calculate basal metabolic rate (BMR), which is the amount of energy expended per day at rest. It was revised in 1984 to be more accurate and was used up until 1990, when the Mifflin-St Jeor Equation was introduced. The Mifflin-St Jeor Equation also calculates BMR, and has been shown to be more accurate than the revised Harris-Benedict Equation. The Katch-McArdle Formula is slightly different in that it calculates resting daily energy expenditure (RDEE), which takes lean body mass into account, something that neither the Mifflin-St Jeor nor the Harris-Benedict Equation do. Of these equations, the Mifflin-St Jeor Equation is considered the most accurate equation for calculating BMR with the exception that the Katch-McArdle Formula can be more accurate for people who are leaner and know their body fat percentage. The three equations used by the calculator are listed below:

Mifflin-St Jeor Equation
(Most Accurate for Most People)

Men:
BMR = 10 × W + 6.25 × H − 5 × A + 5

Women:
BMR = 10 × W + 6.25 × H − 5 × A − 161

Considered the most accurate BMR formula for the general population (except very lean individuals who know exact body fat %).

Revised Harris-Benedict Equation
(1984 version)

Men:
BMR = 13.397 × W + 4.799 × H − 5.677 × A + 88.362

Women:
BMR = 9.247 × W + 3.098 × H − 4.330 × A + 447.593

One of the earliest and still widely used formulas, but generally less accurate than Mifflin-St Jeor for modern populations.

Katch-McArdle Formula
(Uses Lean Body Mass)

BMR = 370 + 21.6 × (1 − F) × W

Best for lean / athletic people who accurately know their body fat percentage (F).

Uses lean body mass instead of total weight, making it more precise when body composition is known.

How Many Calories Do You Need?

Many people seek to lose weight, and often the easiest way to do this is to consume fewer calories each day. But how many calories does the body actually need in order to be healthy? This largely depends on the amount of physical activity a person performs each day, and regardless of this, is different for all people – there are many different factors involved, not all of which are well-understood or known.

Some factors that influence the number of calories a person needs to remain healthy include age, weight, height, sex, levels of physical activity, and overall general health. For example, a physically active 25-year-old male that is 6 feet in height requires considerably higher calorie intake than a 5-foot-tall, sedentary 70-year-old woman. Though it differs depending on age and activity level, adult males generally require 2,000-3000 calories per day to maintain weight while adult females need around 1,600-2,400 according to the U.S Department of Health.

The body does not require many calories to simply survive. However, consuming too few calories results in the body functioning poorly, since it will only use calories for functions essential to survival, and ignore those necessary for general health and well-being. Harvard Health Publications suggests women get at least 1,200 calories and men get at least 1,500 calories a day unless supervised by doctors. As such, it is highly recommended that a person attempting to lose weight monitors their body’s caloric necessities and adjusts them as necessary to maintain its nutritional needs.