The Science of TDEE Simulation
Your Total Daily Energy Expenditure (TDEE) is an estimation of how many calories you burn per day when exercise is taken into account. It is calculated by first figuring out your Basal Metabolic Rate, then multiplying that value by an activity multiplier.
The Mifflin-St Jeor Equation
At Calculators and Simulators, we use the Mifflin-St Jeor formula, widely considered the most accurate for predicting metabolic rates in modern adults:
Men: $$BMR = (10 \times weight) + (6.25 \times height) - (5 \times age) + 5$$
Women: $$BMR = (10 \times weight) + (6.25 \times height) - (5 \times age) - 161$$
Why TDEE Matters
If you eat more than your TDEE, you will gain weight (surplus). If you eat less, you will lose weight (deficit). Understanding this number is the foundation of any successful nutrition or body transformation plan.