TDEE Calculator — Daily Calorie Needs

Quick guide to TDEE

Total Daily Energy Expenditure (TDEE) estimates daily calories combining basal metabolism (BMR) and activity level. Use it as a starting point for adjusting intake to your goals.

How it is calculated

We compute BMR using Mifflin‑St Jeor by default, or Harris‑Benedict if you switch the selector, and then multiply it by an activity factor. You can switch between metric and imperial units at any time.

Form fields

• Age: enter your current age in years.
• Weight and height: choose metric or imperial and add your current measurements.
• Activity: select the option that matches your weekly routine (training and work).

TDEE and weight management

The fundamental principle of weight management is energy balance: the relationship between calories consumed and calories expended (TDEE). If you eat fewer calories than your body uses, you enter an energy deficit and lose weight; if you eat more, you create a surplus and gain weight. Hall et al. (Lancet 2011) developed a validated mathematical model demonstrating that body weight changes are not linear: as you lose weight, your energy expenditure decreases adaptively, slowing the rate of loss. This is why "simple rules" like "3,500 kcal = 0.45 kg" overestimate long-term outcomes. The Mifflin-St Jeor equation (Am J Clin Nutr 1990) is currently the most accurate formula for estimating basal metabolic rate (BMR), the starting point for calculating TDEE. A practical approach is to calculate your TDEE, apply a moderate deficit or surplus (15-20%), and adjust every 2-4 weeks based on real-world progress.

Activity factors: choosing the right level

TDEE is obtained by multiplying BMR by a physical activity level factor (PAL). The five standard levels are: sedentary (×1.2) for desk-based work with no exercise; lightly active (×1.375) if you train 1-3 days per week or walk regularly; moderately active (×1.55) if you train 3-5 days per week at moderate intensity; very active (×1.725) if you train 6-7 days per week at high intensity; and extra active (×1.9) for athletes or jobs demanding heavy daily physical labor. When choosing your level, consider not just planned exercise but all daily activity: commuting, stairs, standing work, household chores. The Compendium of Physical Activities (Ainsworth et al., Med Sci Sports Exerc 2011) assigns MET values to over 800 activities and serves as the reference for classifying movement intensity. If you are unsure between two levels, choose the lower one and adjust based on results.

Basal metabolic rate vs. TDEE

BMR (basal metabolic rate) is the energy your body needs at complete rest to maintain vital functions such as breathing, circulation, and temperature regulation. It accounts for 60-75% of total daily energy expenditure. The second component is the thermic effect of food (TEF), which makes up roughly 10% of the total and refers to the energy used to digest, absorb, and metabolize nutrients. The third component is activity thermogenesis, encompassing both planned exercise and non-exercise activity (NEAT), representing 15-30% of total expenditure. The sum of these three components is your TDEE. A landmark study by Pontzer et al. (Science 2021), drawing on data from over 6,400 people across 29 countries, demonstrated that energy expenditure follows predictable patterns across the lifespan: it remains stable between ages 20 and 60, then declines by approximately 0.7% per year. Understanding the difference between BMR and TDEE is essential: your BMR is the minimum baseline that should never be cut by dieting, while TDEE is the real-world figure against which to adjust your caloric intake.

Interpretation and tips

• Treat it as an initial reference. Adjust every 2‑3 weeks based on progress (weight, energy, satiety).
• For deficit or surplus, use moderate ranges (15‑20%) and avoid extreme cuts.

Practical usage examples

• Fat loss: if your estimated TDEE is 2,200 kcal, a moderate 15‑20% deficit would be around 1,750‑1,870 kcal per day. Keep this target for at least 2‑3 weeks before changing it.
• Maintenance: use your TDEE value as the main reference and check whether body weight stays stable for several weeks.
• Muscle gain: adding roughly 10‑15% above your TDEE is often enough to make progress without gaining too much body fat.

Common mistakes

• Relying on a single estimate and not comparing it against real‑world progress (weight, measurements, performance). Calculations are always an approximation.
• Switching goals every few days. Calorie and activity changes need time before they show up in your body.
• Ignoring context: poor sleep, high stress or health issues can alter true energy expenditure and appetite.