TDEE Calculator – How to Lose Weight Fast

If you want to know how to lose weight fast, then understanding Total Daily Energy Expenditure, along with a TDEE Calculator, is a powerful concept you should acquaint yourself with. TDEE is like the code to effective weight management, helping you understand the energy your body requires daily. In this post we’ll break down how TDEE works to help you lose weight, how to calculate it, include links to TDEE calculators, and how to use it to customize your fitness journey.

Decoding TDEE

Total Daily Energy Expenditure, in simple terms, is the total number of calories your body burns in a day. It’s the sum of three components:

  1. Basal Metabolic Rate (BMR): The calories your body burns at rest, simply to maintain basic functions like breathing and cell repair. Think of BMR as the most basic amount of calories you burn per day just to keep your body going, almost as if you were lying in bed all day with no additional movement or calorie burn.
  2. Thermic Effect of Physical Activity (TEPA): This is the energy used during exercise and daily activities. TDEE accounts for the different daily efforts that different individuals perform throughout the day. For instance, if two people have the same BMR, but one of them works at a physically demanding job while the other spends all day at a desk, then the TDEE will be higher for the physical person vs the sedentary person.
  3. Thermic Effect of Food (TEF): The calories burned during digestion. This has only a minor impact on the TDEE, but it is part of the calculation.

Why TDEE Matters in Weight Loss

No matter what different fitness influencers will tell you, you must create a calorie deficit in order to lose body fat. This means you consume fewer calories than your TDEE, prompting your body to tap into stored fat for energy. The Caloric Deficit can be achieved in three ways:

  1. Reduce the amount of calories you consume per day to be Less than your TDEE.
  2. Increase the amount of calories you burn per day to be Greater than your TDEE.
  3. A combination of both #1 and #2 to achieve the fastest results.

Here’s how you can use TDEE to reach your weight loss goals:

  1. Calculate Your TDEE: Use an online calculator (see links below) or consult a fitness professional to estimate your TDEE. This figure represents the number of calories required to maintain your current weight.
  2. Determine Your Caloric Intake Target: Decide how many calories you want to consume daily for weight loss. It’s fine to start by cutting 250-500 calories to start, or get more aggressive if you are consulting a medical professional or nutritionist.
  3. Build a Workout Plan:
    – Use physical activity or cardio workouts to add an extra 250-500 calories per day of additional calorie burn.
    – Work with a personal trainer or fitness professional to help build a plan that works for you.
    – Consider a mix of cardiovascular exercise, strength training, and flexibility workouts.
    – Use a heart rate monitor or a wearable device to measure the calories you burn per workout. Apple Watches have these built in!
  4. Regularly Monitor Progress: Weight loss isn’t always linear. Track your weight, body measurements, and how you feel throughout your journey. If you’re not experiencing the expected weight loss, consider adjusting your caloric intake or exercise routine.

Real-Life Application of TDEE

Imagine Bob, a 40-year-old computer programmer, as an example. He’s 5′ 9″ tall, weighs 185 pounds, and never works out. His calculated TDEE is 2,087 calories. In this example, let’s assume he tracks his food intake and eats exactly 2,087 calories per day. This means he is stable at his 185 pound weight.

According to the Body Mass Index, this puts Bob at a 27.3 BMI which is considered Overweight by the CDC. He should be under 25 BMI to be in the “Healthy Weight” status as defined by the CDC.  So Bob sets a goal weight of 165 pounds in order to bring his BMI down to a healthy 24.4 BMI. This means he needs to lose 20 pounds – a very achievable goal!

He wants to lose one pound per week, which requires a weekly calorie deficit of 3,500 calories (since one pound equals approximately 3,500 calories). With this plan, he’ll achieve his goal of losing 20 pounds in approximately 20 weeks, or 5 months.

Bob needs to find a way to reduce his TDEE by 500 calories per day. He can do this in three ways:

  1. Change his diet so he’s only consuming 1,587 calories per day.
  2. Begin working out for one about one hour a day to begin burning an extra 500 calories per day.
  3. A combination of #1 and #2. For instance, adding 250 calories worth of cardio per day (about 30 minutes) and reducing his food intake down to 1,837 per day.

Bob realizes he drinks a lot of sugary drinks throughout the day, and that it would be pretty easy to find a way to cut back on 250 calories per day. Also, he’s never worked out, so he’s not up to an hour of cardio per day and wants to start with 30 minutes a day. So Bob goes with option #3.

If Bob sticks with this 500 calorie deficit for 20 weeks, he’ll hit his goal. But – spoiler alert – once Bob gets in the routine of regular workouts and scaling back his diet, he may find it natural to up his cardio sessions from 30 minutes to 45 minutes. Also, he may find himself eating healthier and taking his diet to 1,750 calories a day. This means he might very well achieve his 20 pound weight loss goal much sooner than 20 weeks!

This is how incorporating TDEE into your weight loss journey allows for predictable and science-backed results. It helps you set realistic goals and understand the balance between diet and exercise. Remember, consulting a healthcare or fitness professional can provide you with a more personalized TDEE calculation and specific guidance for your unique situation. With the power of TDEE, you have a valuable tool to make your weight loss journey a success.

How to Calculate Your TDEE

Calculating your TDEE might sound complex, but it’s actually straightforward. There are links to several online calculators below, but it’s based on 5 parameters:

  1. Gender
  2. Age
  3. Weight
  4. Height
  5. Activity Level (generally categorized as)
    1. Sedentary (little or no exercise)
    2. Lightly active (light exercise or sports 1-3 days a week)
    3. Moderately active (moderate exercise or sports 3-5 days a week)
    4. Very active (hard exercise or sports 6-7 days a week)
    5. Super active (very hard exercise, physical job, or training twice a day)

Once you’ve identified your TDEE, you can customize your daily calorie intake. To lose weight, you should consume fewer calories than your TDEE, and to gain weight, more.


  • TDEECalculator.net – A solid, basic TDEE calculator
  • TDEECalculator.org – A more sophisticated TDEE calculator, including some advanced BMR formula variations for MIFFLIN-ST, HARRIS-BENEDICT, etc.

The Power of TDEE

The key to TDEE is tracking your calorie intake. Mobile apps and food diaries are fantastic tools for this. Tracking your intake provides invaluable insights into your eating habits and helps you stay on target.

Remember, TDEE isn’t static. It can change as your weight, activity level, or lifestyle evolves. So, monitoring it periodically is essential.

Your fitness journey is uniquely yours, and understanding TDEE adds an extra layer of knowledge and control. So, if you’re committed to your health and fitness goals, get to know your TDEE. It’s a tool that can guide you toward a fitter, healthier, and happier you.

Also, don’t forget to track your calories burned during your workouts! Pick up an Apple watch from Amazon, or click here to read our review of budget-friendly heart rate monitors.

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