Estimate basal metabolic rate and daily calories using established equations and activity factors. Runs locally in your browser.
Added Apr 18, 2026 · Updated May 1, 2026
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Calculates your Basal Metabolic Rate (BMR) — calories burned at complete rest — using the Mifflin-St Jeor equation, then multiplies by an activity factor to get your Total Daily Energy Expenditure (TDEE). This is your estimated daily calorie maintenance level.
BMR (male) = 10·W + 6.25·H − 5·A + 5 | BMR (female) = 10·W + 6.25·H − 5·A − 161
BMR = 10×70 + 6.25×175 − 5×30 + 5 = 1,649; TDEE = 1,649 × 1.55 ≈ 2,556.
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BMR (Basal Metabolic Rate) is the calories your body burns at complete rest just to maintain basic functions. TDEE (Total Daily Energy Expenditure) adds the calories burned through activity. TDEE is your maintenance calorie level.
The Mifflin-St Jeor equation is accurate to within ~10% for most adults. Factors it cannot account for include muscle mass, metabolic conditions, medications, and precise activity tracking. Use it as a starting point and adjust based on real-world results.
Choose the band that reflects an average week, not your best week. If you lift heavy 4× but sit at a desk otherwise, 'moderate' is often more realistic than 'very active'. Track weight trend for 3–4 weeks and nudge the multiplier up or down.
Wearables estimate active burn differently and may double-count steps plus workouts. Treat them as correlated signals, not ground truth. Align calories to scale trend and performance goals instead of chasing perfect agreement.