TDEE Calculator - Calculate Total Daily Energy Expenditure (2024)

Quick navigation:

1. Notes on the TDEE calculator output
2. What is TDEE and why it matters
3. Estimating Total Daily Energy Expenditure
4. TDEE formula
5. TDEE and losing weight
6. How many calories do you need?

Notes on the TDEE calculator output

TDEE metrics used: 1 Calorie = 1 kcal (1 kilocalorie) = 1,000 calories. A single asterisk (*) accompanies the calorie intake estimation denoting that this is a rough guideline. We recommend you use our calorie calculator for weight loss for a much more precise estimate.

What is TDEE and why it matters

TDEE stands for Total Daily Energy Expenditure and it is a measure of how much energy in Calories or kilocalories (kcal) you expend during your day and this is exactly what our TDEE calculator helps you estimate. There are three main things that affect it: physical activity, dietary-induced thermogenesis, and the climate you spend your day in. For women pregnancy is also a factor as it increases the energy cost of physical activities. Of the three, the most profound is the effect of physical activity - usually between 15 - 30% of TDEE ^[1].

Your diet comes in at second place due to the thermic effect of food on total energy expenditure. Its range is between 10-13% of the energy provided by the food. Hot climate can increase your TDEE by 5-20%, but cold climate can have similar effects due to shivering and increased metabolism to maintain core temperature.

Body size and body composition both play a role in your TDEE and this is reflected in the output of our calculator. For example, women tend to have a higher percentage of body fat and smaller muscle mass, resulting in lower energy expenditure relative to their weight. Age is also a factor, with older individuals expending less energy than individuals of the same weight and gender of a younger age as you will note if you enter a different age in our online total daily energy expenditure calculator.

Daily energy expenditure estimates are used in a variety of clinical settings as well as sports / fitness activities. TDEE is also a useful predictor for your daily water intake requirements.

Estimating Total Daily Energy Expenditure

To determine the TDEE one needs to estimate or know:

• the resting metabolic rate (includes basal and sleeping conditions and the cost of staying awake)
• the thermogenic influence of any food consumed during the day
• the energy expended during physical activity and post-activity recovery (physical work, sports training, etc.)

The basal metabolic rate (BMR) is the minimum energy requirement to stay alive and awake. It is measured by the oxygen uptake under strict conditions, namely: no food consumed and no undue muscle exertion in the 12 hours preceding the measurement; the measurement is taken after 30-60 min of resting or lying quietly in a temperature neutral environment ^[2]. Values measured this way are only slightly lower than the resting metabolic rate (RMR), which is measured under less strict conditions. You can use our Basal Metabolic Rate Calculator and our Resting Metabolic Rate Calculator to do these calculations, but if you are only interested in total daily energy expenditure, it is unneeded. See TDEE vs BMR for more on the differences.

Body surface area (BSA) and Body Mass Index (BMI) are sometimes used to estimate TDEE. Accurate measurement of BSA is a challenge, so usually estimations are used, based on studies, while BMI is mathematically defined, so no estimation is needed.

Our software uses body mass, stature, gender, and age to predict resting daily energy expenditure (RDEE). To calculate TDEE it then combines the outcome with the level of exercise you specify to arrive at an accurate total daily energy expenditure estimate ^[1] in Calories. To accurately calculate your TDEE it is important to correctly specify your activity level since it has a multiplicative effect. Fitness and bodybuilding practitioners and professional athletes should be especially careful in selecting their physical activity level for best results.

TDEE formula

The formula used to calculate TDEE in this daily energy calculator is: TDEE = BMR x Activity Multiplier, where BMR is calculated using:

BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age(y) + s

where s is a gender constant set at 5 for males and -161 for females. The activity multipliers are averages and thus the whole result of the TDEE calculation might be skewed if you select an exercise level that doesn't correspond to your actual energy expenditure during workout.

TDEE and losing weight

Knowing your TDEE is a great way to control your weight. Even estimating it with a tool like our total daily energy expenditure calculator, while not as precise as medically accurate procedures, is still much better than eyeballing since many people do not have an accurate idea of how much energy they need. This in term leads to a widespread obesity problem some people claim is of epidemic proportions especially in the West. Understanding what factors influence energy expenditure - as explained above and elsewhere is also a good start, so if you are not yet asking yourself "how many calories should I eat a day?", you should!

Our TDEE calculator automatically converts the energy you expend per day to Calories (1 Calorie = 1 kcal = 1,000 calories), so in fact it tells you how many calories you need per day - in other words, how many calories you should eat to maintain weight. Then you can use a macro calculator to come up with a good mix of proteins, carbs and fats for your diet.

If you need to know how many calories to eat to lose weight, our calculator shows you exactly that: it displays how many calories per day to consume to lose 1 or 2 pounds per week (0.5 - 1 kg per week), assuming you maintain your current exercise level. Don't stretch yourself and do not forget that having a diet you can follow every day, no exceptions, is key in permanently losing weight.

Alternatively, you can explore how increasing your physical activity level can increase your energy expenditure and thus assist in weight control or weight loss. Just select a different activity level in our online tool and watch the numbers shift. Finding a good compromise between a healthy diet and a good, but not risky exercise level is a must.

You should beware not to use naked BMR to base your food consumption on, as it will significantly underestimate the required calorie intake, leading to negative consequences such as malnourishment.

Finally, while you may get the mathematics of weight loss right, there is a psychological and emotional component to the process which should not be underestimated. Knowing your TDEE is useless if you cannot find the will and motivation needed to keep to a strict regime over prolonged time.

How many calories do you need?

The TDEE calculator shows your energy expenditure per day in Calories per day (equal to kcal per day). This is the amount you need to preserve your current weight. The tool then shifts that up or down to show you estimates of the recommended caloric intake to achieve a certain weight goal, assuming you maintain your current exercise level. It is a good idea to keep track of your weight as you go and adjust accordingly.

Here are some averages for different ages and age groups of both genders calculated using our calculator based on weight and height data from the U.S. NCHS National Health and Nutrition Examination Survey (2011-2014) ^[3] and assuming light physical activity.

It is easy to see that total daily energy needs increase with age to about 20-25 years of age, and then decline slightly, but steadily as one ages. Males of all age groups require 10-20% more calories per day, on average, which is reflected in the math equations used in the tool.

The above are just general guidelines and you should always consult with your physician or nutritionist before undertaking a diet or a significant change to your dietary and exercise routine based on calculated TDEE.