TDEE Calculator
Estimate your true daily burn: Mifflin-St Jeor BMR multiplied by a standard activity factor from 1.2 to 1.9. This is the maintenance number every deficit or surplus is built around.
Members: the Phorme app recalculates this automatically as you log.
Baseline first, then multiply.
TDEE stacks everything you burn in a day on top of your basal metabolic rate: digestion, structured training, and all the walking, standing, and fidgeting in between. Measuring each piece directly takes a metabolic chamber, so the practical method compresses them into one multiplier.
We compute BMR with the Mifflin-St Jeor equation (1990), then multiply by a standard activity factor: 1.2 for sedentary through 1.9 for hard daily training plus a physical job. These factors trace back to the activity classifications long used alongside predictive BMR equations in nutrition practice.
The multiplier is where most error lives. People overestimate their activity more often than their BMR is wrong, so the results table shows your TDEE at every level. If fat loss stalls at your chosen number, read one row down before blaming your metabolism.
- 1. Enter your age, sex, height, and weight.
- 2. Pick the activity level that matches your average week. When in doubt, pick the lower one.
- 3. Press Calculate to get your BMR and TDEE, plus your TDEE at every activity level.
- 4. Hold intake near TDEE for two weeks and watch the scale: flat weight confirms the number.
BMR: Mifflin-St Jeor (1990): 10W + 6.25H minus 5A, +5 male / minus 161 female.
TDEE: BMR x activity factor: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 extra active.
Questions we hear a lot.
Which activity level should I pick?
Count structured training and your job together, and when in doubt pick the lower option. Most lifters with desk jobs who train 3 to 5 days a week land at moderate (1.55). Overshooting the multiplier is the most common way these calculators run high.
How is this different from what my watch reports?
Wrist devices estimate calories from heart rate and movement models, and validation studies routinely find daily errors of 10 percent or more. A formula-based TDEE is also an estimate, but it is stable, which makes it a better anchor. Trust the trend in your body weight over either number.
My weight is not moving at my calculated TDEE. Is the number wrong?
It is a starting estimate with roughly a 10 percent error band in either direction. Hold a fixed intake for two weeks: if weight stays flat, that intake is your real TDEE. Adjust the number, keep the method.
Does TDEE change while I diet?
Yes, in two ways. A lighter body burns fewer calories, and a prolonged deficit modestly reduces non-exercise movement. Recalculate as weight changes and expect to nudge intake down over a long cut.
What are the components of TDEE?
Basal metabolic rate, the thermic effect of food, exercise activity, and non-exercise activity thermogenesis (NEAT). The activity multiplier bundles the last three on top of BMR in a single factor.
One plan. Training and recovery in one system.
Phorme builds the plan from what you log and how you recover. No spreadsheets. No guessing.