Estimate daily energy use from BMR and activity. Provide body fat % to use Katch–McArdle; otherwise we use Mifflin–St Jeor.
Total Daily Energy Expenditure (TDEE) is the amount of energy your body uses across a full day, combining what you burn at rest and what you burn while moving, thinking, training, digesting, and recovering. Knowing this number gives you a practical anchor for meal planning and progress tracking. The calculator above estimates your BMR from personal details, scales it by an activity factor, and returns an everyday target in calories. The estimate isn’t a rigid prescription—it’s a starting point that becomes more accurate as you compare it with your real-world results.
Activity multipliers are simple on purpose. They aim to place your average day into a bucket. If you’re on the fence between two options, pick the lower one and retest in a couple of weeks. A lower starting point often prevents the frustration of overshooting and having to course-correct by a large amount.
Mifflin–St Jeor works well for many adults because it was developed on modern populations and rarely overshoots by a wide margin. Katch–McArdle can be better if body composition is far from average—very lean strength athletes, or higher body fat with lower lean mass. If you have a reasonable body fat estimate (from calipers, circumference method, DEXA, or a well-calibrated device), turning on the body-fat field lets the calculator shift to Katch–McArdle automatically.
TDEE is a maintenance estimate—eat roughly this amount and your weight trend should hold steady over time. To lose or gain, adjust around this baseline. Small, steady changes are easier to maintain than big swings. For fat loss, a modest deficit (for example, 250–500 calories per day) is a common starting range; for gaining, a similar surplus often supports progress without excessive fat gain.
If you prefer structure, you can convert your calories into protein, fat, and carbohydrate targets. Many people do well with a balanced split that emphasizes protein for satiety and recovery, allocates fats for hormones and cell health, and places most carbs around training and busier periods of the day. Others keep it simpler by anchoring protein first and letting carbs and fats float with appetite and activity.
Example 1: A 30-year-old male, 5′10″ and 175 lb, trains four days a week and averages 8–10k steps. His Mifflin–St Jeor BMR is ~1,740 calories/day. With a “Moderate” multiplier (1.55), his TDEE is ~2,700 calories/day. He aims to maintain performance while leaning out slowly, so he tries ~2,450 calories for a couple of weeks and monitors weight, waist, and gym performance.
Example 2: A 38-year-old female, 165 cm and 68 kg, estimates body fat at 24%. Katch–McArdle sets BMR near 1,420 calories/day. With “Light” activity (1.375), TDEE comes out around 1,950 calories/day. She’s feeling low energy, so she targets maintenance for two weeks before considering a small deficit.
Do I need to hit the same number daily? No—think in weekly averages. Eating a little more on training days and a little less on rest days works well.
Which formula is “most accurate”? Both are estimates. Use the one that best matches your situation, then adjust based on real progress.
Can wearables replace this? Devices can help, but they also estimate. Combining this calculation with observed trends gives the most reliable picture.
Educational purposes only; not medical or nutrition advice. If you have a medical condition, consult a qualified professional.
What is TDEE?
Total Daily Energy Expenditure (TDEE) is the estimated number of calories you burn in a day based on your basal metabolism plus your daily activity.
How do you calculate TDEE?
First estimate your BMR (e.g., Mifflin–St Jeor), then multiply it by an activity factor that matches your lifestyle (sedentary → very active).
Which BMR formula should I use?
Mifflin–St Jeor is a solid default for most people. If you know body-fat %, Katch–McArdle can personalize BMR using lean mass.
How accurate is TDEE?
It’s an estimate. Use it as a starting point, then adjust calories based on 2–3 weeks of weight and measurement trends.
What activity level should I pick?
Choose the description that reflects your average week (job + exercise), not a single busy or quiet day.
How do I use TDEE to lose or gain weight?
For loss, aim for a daily intake below TDEE (e.g., −250 to −500 kcal). For gain, eat above TDEE (+200 to +400 kcal). Reassess every few weeks.
Should I recalculate TDEE?
Recalculate when your weight changes by ~2–3% or your activity routine meaningfully shifts.
Example 1 — Maintenance target
A 30-year-old male, 180 lb (82 kg), 70 in (178 cm), “Moderate” activity. BMR ≈ 1,780 kcal/day. TDEE ≈ 1,780 × 1.55 ≈ 2,760 kcal/day for maintenance.
Example 2 — Slow fat loss
If maintenance is ~2,400 kcal/day, a modest deficit of 300 kcal/day targets ~0.5 lb/week loss. Daily target ≈ 2,100 kcal/day.
Example 3 — Lean mass gain
If maintenance is ~2,600 kcal/day, add a 250 kcal surplus to support training and recovery. Daily target ≈ 2,850 kcal/day.