In this article
Two numbers sit behind almost every diet plan: BMR and TDEE. Understanding the difference helps you set realistic calorie targets โ and avoid crash diets that backfire.
This article is general information, not medical or dietary advice. If you are pregnant, have a medical condition, or are planning major diet changes, consult a doctor or registered dietitian.
BMR: the energy to stay alive
Basal Metabolic Rate (BMR) is the energy your body uses at complete rest โ breathing, pumping blood, maintaining body temperature, repairing cells and powering your brain. Even lying in bed all day, you would burn roughly your BMR.
BMR typically makes up 60โ70% of the calories you burn each day. It depends mainly on body size, muscle mass, age and sex.
The Mifflin-St Jeor formula
This equation is widely used because it is reasonably accurate for most healthy adults:
Men: BMR = 10 ร weight (kg) + 6.25 ร height (cm) โ 5 ร age + 5
Women: BMR = 10 ร weight (kg) + 6.25 ร height (cm) โ 5 ร age โ 161
Example: a 30-year-old man, 170 cm, 70 kg:
10 ร 70 + 6.25 ร 170 โ 5 ร 30 + 5 = 1,618 kcal/day.
A 30-year-old woman, 160 cm, 58 kg: 1,269 kcal/day.
TDEE: everything you burn in a day
Total Daily Energy Expenditure (TDEE) adds the calories you burn moving, working, exercising and even digesting food. Itโs estimated by multiplying BMR by an activity factor:
| Activity level | Multiplier | Man in our example | Woman in our example |
|---|---|---|---|
| Sedentary (desk job, little exercise) | 1.2 | 1,941 kcal | 1,523 kcal |
| Light (exercise 1โ3 days/week) | 1.375 | 2,224 kcal | 1,745 kcal |
| Moderate (3โ5 days/week) | 1.55 | 2,507 kcal | 1,967 kcal |
| Active (6โ7 days/week) | 1.725 | 2,790 kcal | 2,189 kcal |
| Very active (physical job or twice-daily training) | 1.9 | 3,073 kcal | 2,411 kcal |
TDEE is the number of calories that keeps your weight stable.
Most people overestimate their activity level. If you have a desk job and go to the gym three times a week, โlightโ is often more accurate than โmoderateโ.
Setting a calorie target
- To maintain weight: eat around your TDEE.
- To lose weight: eat about 300โ500 kcal below TDEE. For many people, a 500 kcal daily deficit leads to roughly 0.5 kg loss per week.
- To gain weight or muscle: eat about 250โ500 kcal above TDEE, ideally with strength training.
Keep your intake above your BMR in most cases โ very low intakes are hard to sustain and can cost you muscle.
Why your real numbers may differ
Formulas estimate the average person with your measurements. Your real burn can differ because of:
- Muscle mass โ more muscle means a higher BMR.
- Genetics and hormones, including thyroid function.
- NEAT (non-exercise activity) โ walking, standing, fidgeting. It can vary by hundreds of calories between people.
- Tracking errors โ portion sizes and cooking oil are easy to underestimate.
The practical solution: follow your target for 2โ3 weeks, track your weight trend, and adjust by 100โ200 kcal if needed.
Make your calories count
Calories decide weight change, but food quality decides how you feel:
- Prioritise protein (dal, paneer, eggs, curd, chicken, fish) to stay full and protect muscle.
- Fill half your plate with vegetables.
- Watch liquid calories โ sugary tea, juices and soft drinks add up quickly.
- Combine diet with strength training to keep muscle while losing fat.
Find your numbers
Our BMR & Calorie Calculator uses the Mifflin-St Jeor equation to estimate your BMR and TDEE for your activity level, and suggests targets to lose, maintain or gain weight โ never dropping below your BMR.
Free toolTry the BMR & Calorie CalculatorEstimate how many calories your body burns at rest and through the day.Frequently asked questions
Should I eat below my BMR to lose weight faster?
Generally no. Eating below your BMR for long periods can cause muscle loss, fatigue and nutrient gaps, and is hard to sustain. A moderate deficit from your TDEE is safer.
Why did my weight loss slow down?
As you lose weight, your BMR and TDEE fall a little, so the same intake creates a smaller deficit. Recalculate every few kilos lost.
Do I need to count calories forever?
No. Many people track for a few weeks to learn portion sizes, then switch to simpler habits like balanced plates and regular activity.
Written by the Toolsopedia team. Spotted an error? Tell us and weโll fix it.