TDEE Maintenance Calculator — Find and Verify Your Weight Stability Point

What TDEE Represents

Your Total Daily Energy Expenditure (TDEE) is the total amount of energy your body uses in a complete 24-hour period. It combines the energy needed to keep your body running at rest (BMR) with the additional energy burned during digestion, movement, exercise, standing, walking, and all other activity. TDEE is the number that, when matched by calorie intake, leads to stable body weight over time. Every calorie-based goal — intentional loss, maintenance, or intentional gain — starts from this anchor number.

The Two-Part Formula

Understanding the 6 Activity Bands

The six activity bands correspond to the widely cited Mifflin-St Jeor scaling levels. Sedentary (1.2) describes a largely seated day with no structured exercise and limited walking. Lightly Active (1.375) adds 1–3 days of light exercise or daily walking and steps over roughly 5,000–7,000. Moderately Active (1.55) corresponds to 3–5 days per week of structured exercise — a common baseline for many regular gym-goers and active commuters. Active (1.725) implies 6–7 days of exercise or a job that keeps you on your feet most of the day. Very Active (1.9) combines daily hard training with a physical role or frequent movement, and Athlete (2.0) reflects elite volume, often two daily sessions.

How the Rate Grid Is Built

From your maintenance TDEE, the eight-card grid applies standard weekly rate adjustments. Each pound per week of weight change is converted to per-day calorie shifts using the 3,500 kcal/lb convention: 0.25 lb/week ≈ ±125 kcal/day, 0.5 lb/week ≈ ±250 kcal/day, 1.0 lb/week ≈ ±500 kcal/day, 1.5 lb/week ≈ ±750 kcal/day, and 2.0 lb/week ≈ −1,000 kcal/day (loss-side only). Gain-side rates are capped at 0.5 lb/week in the default grid because faster gains tend to disproportionately increase fat storage rather than lean tissue for most natural non-elite trainees.

Why Prefill via ?bmr=

The optional URL prefill from the BMR Calculator lets you compare formulas on the BMR page, pick the one that best matches your context (for example, using Katch-McArdle if you know body composition), and then carry that specific BMR value forward to the TDEE page. In prefill mode, gender / age / height / weight inputs still update on-screen BMR for reference, but the core TDEE anchor comes from the URL value you brought in. This gives you flexibility to work with your own BMR estimate, indirect calorimetry reading, or wearable-device estimate of daily burn.

Known Limitations of TDEE Math

Population-level equations miss individual variation. Muscle mass, genetics, thyroid function, hormonal cycles, caffeine and stimulant intake, sleep quality, gut absorption, Rx items, body composition adaptations, and even minor unplanned fidgeting can shift real daily burn by hundreds of calories in either direction. The calculator is a reference starting point, not a measured truth. Validating against 2–3 weeks of actual weight data while tracking intake is the most reliable way to refine the number for your unique body.

Why TDEE Equals Maintenance

Total Daily Energy Expenditure (TDEE) is, by definition, your maintenance calorie level — the daily intake at which body weight stays stable over time. TDEE sums basal metabolic rate, activity energy expenditure, the thermic effect of food, and adaptive thermogenesis into a single daily number. If you eat at TDEE, weight stays stable. If you eat above TDEE, weight climbs. If you eat below TDEE, weight drops. Every calorie deficit or surplus plan starts with knowing your TDEE, because every deficit or surplus is calculated relative to it. Without an accurate TDEE estimate, any calorie target you set is essentially a guess.

Calculating TDEE for Maintenance

The chain from BMR to TDEE has two steps. First, calculate your BMR using a validated formula such as Mifflin-St Jeor. Second, multiply BMR by an activity factor (1.2 sedentary, 1.375 lightly active, 1.55 moderately active, 1.725 very active, 1.9 athlete) to get TDEE. Activity factor selection is the single biggest source of error in the calculation — most people overestimate their activity level. When in doubt, pick the lower multiplier and refine based on observed weight trend over 2 to 4 weeks.

The Weight Stability Validation Method

The most reliable way to verify your TDEE estimate is the weight stability method. Eat at your estimated TDEE for 2 consecutive weeks under consistent conditions — same sleep schedule, same training schedule, same general food choices. Weigh yourself 3 mornings per week and use the weekly average. If your 2-week average weight stays within ±0.5 kg of starting weight, your estimate is close to true maintenance. If weight drops more than 0.5 kg, your true TDEE is higher than the estimate — add 100 to 200 kcal per day. If weight climbs more than 0.5 kg, your true TDEE is lower — subtract 100 to 200 kcal per day.

Why TDEE Shifts Over Time

TDEE is not a fixed number. It shifts with body weight (heavier bodies burn more calories at rest and during activity), body composition (more muscle raises BMR), age (BMR declines roughly 100 to 150 kcal per decade after age 30), season (cooler weather slightly raises expenditure through thermoregulation), training phase (high-volume weeks burn more than deload weeks), and hormonal status. Perimenopause, menopause, thyroid changes, and many other hormonal shifts can move TDEE by 200 to 500 kcal per day. Consider TDEE a moving target rather than a fixed number, and re-calculate every 4 to 6 weeks.

Practical Tracking Tips

• Weigh yourself 3 mornings per week under consistent conditions and use the weekly average. Daily readings are noisy due to hydration, sodium, and digestive contents.
• Re-calculate TDEE every 4 to 6 weeks as body weight and activity shift. Consider TDEE a moving target, not a fixed number.
• Track hunger, energy, and training quality alongside weight. If all three stay stable while weight is stable, your TDEE estimate is solid.
• Reassess after major life transitions (new job, new baby, new sport, perimenopause). Each can shift TDEE by 200 to 500 kcal per day.
• Pair scale weight with how your clothes fit, waist circumference, and progress photos. These markers often surface shifts before the scale does.