Resting Calorie Calculator

Resting Calorie Calculator UK 2026 | BMR & Daily Calorie Needs Estimator
calculatorsonline.co.uk

Resting Calorie Calculator

Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Find out exactly how many calories your body burns at rest and how many you need each day.

🔥 BMR at Rest
📊 TDEE by Activity
🥗 Calorie Goals
🏥 Mifflin-St Jeor Formula

BMR & Resting Calorie Estimator

Uses the Mifflin-St Jeor equation — the most accurate formula for most adults

Personal Details

Biological sex affects BMR due to differences in muscle mass and hormones.

Enter your age in whole years. BMR decreases gradually with age.


Measurements

Measure without shoes, standing straight.

Measure in light clothing, without shoes.


Activity Level

Choose the level that best describes your typical week. This calculates your TDEE (total calories needed per day).


Display Options

Calorie Result

Basal Metabolic Rate & Daily Energy Needs

🔥

Enter your details and click Calculate Calories to see your resting calorie burn, TDEE, and personalised calorie goals.

Average BMR by Age & Sex

Estimated average Basal Metabolic Rates for adults by age group and sex, based on average UK height and weight data and the Mifflin-St Jeor formula. Individual results will vary based on your exact measurements and body composition.

Age Group Average BMR (Men) Average BMR (Women) Sedentary TDEE (Men) Sedentary TDEE (Women)
18–25 years1,850 kcal1,530 kcal2,220 kcal1,836 kcal
26–35 years1,800 kcal1,490 kcal2,160 kcal1,788 kcal
36–45 years1,750 kcal1,450 kcal2,100 kcal1,740 kcal
46–55 years1,700 kcal1,410 kcal2,040 kcal1,692 kcal
56–65 years1,640 kcal1,360 kcal1,968 kcal1,632 kcal
66+ years1,570 kcal1,300 kcal1,884 kcal1,560 kcal

Resting Calories & BMR FAQ

Everything you need to know about resting calorie burn, basal metabolic rate, and how to use your results.

Basal Metabolic Rate (BMR) is the number of calories your body needs to perform its most basic life-sustaining functions — breathing, circulation, cell production, and temperature regulation — while completely at rest. It represents the minimum amount of energy your body requires to simply stay alive, typically accounting for 60 to 75 percent of your total daily calorie expenditure.

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor to account for the calories burned through daily movement and exercise. TDEE is the total number of calories you need to consume each day to maintain your current weight.

This calculator uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for estimating BMR in the general population. It was developed in 1990 and is the formula recommended by the British Dietetic Association. The formula takes into account your weight, height, age, and sex.

The average adult burns between 1,400 and 2,000 calories per day at rest (BMR), depending on their age, sex, height, and weight. Men typically have a higher BMR than women due to greater muscle mass. A larger body mass and greater height also increase BMR. As you age, your BMR tends to decrease gradually.

To lose weight, you need to consume fewer calories than your TDEE (creating a calorie deficit). A deficit of approximately 500 calories per day typically results in a loss of around 0.5 kg per week. To gain weight or build muscle, you need to consume more calories than your TDEE (creating a calorie surplus). Always consult a healthcare professional or registered dietitian before making significant changes to your diet.

Yes. Muscle tissue burns significantly more calories at rest than fat tissue. This is why people with greater muscle mass have a higher BMR. Strength training and resistance exercise can increase your muscle mass over time, which raises your resting metabolic rate and means you burn more calories even when not exercising.

Online BMR calculators provide a useful estimate, but they cannot account for individual variations in body composition, genetics, hormonal factors, and metabolic health. The Mifflin-St Jeor formula has an accuracy range of plus or minus 10 percent for most people. For a precise measurement of your resting metabolic rate, a clinical indirect calorimetry test would be needed.

Similar Posts