TDEE Calculator

Your Total Daily Energy Expenditure (TDEE) is calculated in two stages. First, the calculator determines your Basal Metabolic Rate (BMR)—the number of calories your body needs just to sustain basic life functions like breathing, circulation, and cell repair while completely at rest. The most widely validated formula for this is the Mifflin-St Jeor equation, which takes your weight, height, age, and biological sex as inputs. An older alternative, the Harris-Benedict equation, is also sometimes used but tends to overestimate slightly for modern, more sedentary populations.

Once your BMR is established, it is multiplied by an activity multiplier—commonly called the Physical Activity Level (PAL)—to account for everything you do beyond lying still. These multipliers range from approximately 1.2 for a sedentary desk worker who rarely exercises, up to 1.9 or higher for athletes in heavy daily training. Choosing the right activity level is the single biggest source of user error: most people overestimate how active they are, which inflates their TDEE and causes unintended weight gain even on a 'diet.' If you are unsure, it is almost always smarter to start one level lower and adjust based on real-world results over two to four weeks.

From your maintenance calories—the TDEE figure itself—the calculator then derives two additional targets. A caloric deficit (cut) is typically set at 300–500 kcal below TDEE, which is the evidence-based range for losing roughly 0.5–1 lb of fat per week while preserving lean muscle mass. A caloric surplus (bulk) is set at 250–500 kcal above TDEE to support muscle protein synthesis without excessive fat accumulation. These ranges matter: too aggressive a cut raises cortisol and accelerates muscle loss, while too large a surplus mostly produces fat rather than muscle—a concept sometimes called 'dirty bulking.'

A critical detail many users overlook is that TDEE is not a fixed number—it changes as your body adapts. When you lose weight, your BMR drops because there is less tissue to maintain, and your body may also reduce non-exercise activity thermogenesis (NEAT) as a compensatory mechanism. This is why fat loss plateaus happen even with consistent dieting. The practical fix is to recalculate your TDEE every 4–6 weeks or whenever your weight changes by more than 5–10 lbs, and to adjust your calorie targets accordingly. Treating TDEE as a living estimate rather than a permanent prescription is what separates effective long-term dieters from those who stall indefinitely.