Maintenance Calorie Calculator

Your weight maintenance calorie intake is the amount of calories you can eat each day to maintain a stable body weight. At this level of intake your weight will remain stable; eating less than this will cause weight loss and more will cause weight gain.

This value is also known as the Total Daily Energy Expenditure (TDEE). It's the sum of energy your body uses at rest and during daily activities. Knowing this number allows you to turn vague advice like "eat less" into specific, everyday numbers that can form a plan.

What is your calorie requirement for weight maintenance?

Calculating your calorie needs for weight maintenance begins with your Basal Metabolic Rate, or BMR. This is the amount of energy required to maintain basic life functions such as breathing, blood circulation, body temperature and functioning of all organs. The BMR accounts for about 60-70% of total energy expenditure in most people.

In addition to this, the body burns energy through daily activities and movement. A tool for calculating calorie needs for weight maintenance multiplies BMR by an activity factor to account for these expenditures, resulting in TDEE.

Here's how to use this calculator.

Enter your gender, age, height and weight and select the activity level that matches your typical week's routine. The calories required to maintain your weight will be shown along with your Basal Metabolic Rate (BMR).

Here you can make further adjustments. If you know your body fat percentage, you can switch the formula to Katch-McArdle. By enabling Body Weight Goal, calorie needs for weight maintenance are converted into a deficit or surplus based on a safe weekly rate of change. By enabling Macros, target calories will be split into grams of protein, carbs and fat.

Three formulas for basic metabolism rate (BMR)

This calculator uses three different formulas. For average body types the results are very similar but for extreme body types there may be slight differences so choose the formula that most closely matches your input data.

Mifflin-St Jeor (recommended)

This formula was published in 1990 and is used by most nutritionists today. Compared to older formulas it more accurately reflects the state of the body of modern humans. You need your weight, height, age, and gender.

where w is weight in kilograms, h is height in centimeters and a is age in years. For a man aged 30 with a weight of 80 kg and a height of 180 cm the BMR would be about 1,780 kcal.

The revised Harris-Benedict formula:

The history of the Harris-Benedict formula goes back to 1919 and was revised in 1984. It is a classic formula, where the calculated values are somewhat higher than with the Mifflin-St Jeor formula for many people.

The Katch-McArdle formula.

This formula is based on lean body weight and not total weight which makes it perhaps the most accurate formula when body fat percentage is known. As it is based on lean body weight, it does not use the gender variable directly.

The lean body weight is calculated by multiplying the weight with the complement of the percentage of body fat in decimal form. For a weight of 80kg and a body fat percentage of 20%, the lean body weight would be 64kg, and BMR would be about 1752kcal.

Activity level

The activity factor is multiplied by the BMR to reflect your level of physical activity. Be sure to pick a value that matches your actual activity level, as most people tend to overestimate their own activity. The following table shows the multipliers used in this calculator:

Convert your weight maintenance calorie needs to a goal

If you want to lose weight, take in less than your BMR; if you want to gain weight, take in more. Body fat stores about 3500 calories per pound or about 7700 calories per kilogram so the rate of change will depend on your daily calorie deficit.

A daily deficit of 500 calories is a common goal and will result in weight loss of about one pound per week. A deficit of 250 calories per day is more moderate and easier to maintain, while a deficit of 1,000 calories per day is very strict and may be difficult to sustain long term, especially if you want to gain muscle mass.

Many guidelines state that women should not consume fewer than about 1200 calories per day and men should not consume fewer than about 1500 calories per day without medical supervision, as going lower can be counterproductive in addition to failing to meet nutritional needs. This calculator limits your weight loss goals to this calorie range and will show a warning if you go below it.

Proteins, carbohydrates and fats.

Calories tell you how much to eat while macronutrients tell you what those calories are made of. Protein and carbohydrates both provide 4 calories per gram whereas fat provides 9 calories per gram.

Protein is most important during weight loss. A high protein diet is popular for preserving muscle and promoting satiety, especially when calories are limited. The macronutrient options selected here will convert the target calories into grams of protein, carbs, and fat depending on your chosen diet.

How accurate are these results?

The formulas used here are estimates and not actual measurements. Even if two people have the same height, weight, age, and gender, their actual metabolism can vary due to factors such as genetics, muscle mass, and hormones.

Use these values as a reliable starting point. Eat for two to three weeks at the estimated calories for weight maintenance and record your weight before adjusting your calorie intake by 100-200 calories based on actual changes. Your own changes are the most accurate calculation tool.