1. Get your number
Fill in the five inputs. Be honest about activity level — most desk workers who train 3 times a week belong in "1–3×/week", not higher.
Free online tool
TDEE calculator: your daily calorie needs.
Total Daily Energy Expenditure is the number every eating plan starts from. Enter age, sex, height, weight, and how active you are to get your maintenance calories, plus ready-made targets for losing or gaining. The activity level is the biggest lever — StepDay shows you what yours actually looks like.
How to use it
How to use your TDEE.
Calculate once, verify with the scale, adjust in small steps.
2. Pick a goal target
Maintain at your TDEE, lose at −15%, gain at +10%. Larger deficits work briefly but are hard to sustain and cost muscle.
3. Verify for 2–3 weeks
Weigh yourself a few mornings a week. If the trend doesn't match the goal, adjust by ±100 kcal and re-verify — your real TDEE is what the scale says it is.
Reference
The numbers behind the tool.
Formulas, reference tables, and practical guidance you can come back to.
The Mifflin-St Jeor formula
BMR for men = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5. For women, the same with −161 instead of +5. TDEE = BMR × activity multiplier. Example: a 30-year-old man, 175 cm, 70 kg, training 1–3 times a week: BMR ≈ 1,649 kcal, TDEE ≈ 1,649 × 1.375 ≈ 2,270 kcal.
Activity multipliers
Multipliers describe your whole day, not just workouts — a construction worker who never exercises can out-burn a desk worker who trains daily.
| Lifestyle | Multiplier | Typical day |
|---|---|---|
| Sedentary | 1.2 | Desk job, under ~5,000 steps, no training |
| Lightly active | 1.375 | Training 1–3×/week or ~7,500 steps |
| Moderately active | 1.55 | Training 3–5×/week or 10,000+ steps |
| Very active | 1.725 | Training 6–7×/week or a physical job |
Setting a deficit or surplus that sticks
A 15% deficit (roughly 300–450 kcal for most people) loses about 0.25–0.5 kg per week while keeping training quality and muscle. For gaining, +10% adds muscle with minimal fat for most lifters. Recalculate whenever your weight changes by ~5 kg or your routine changes season — TDEE is a moving target.
FAQ
Frequently asked questions.
Quick answers about this tool and how to train with it.
What is TDEE exactly?
Total Daily Energy Expenditure: everything you burn in 24 hours. It's your BMR (calories burned at complete rest, ~60–70%) plus daily movement, formal exercise, and the energy cost of digesting food (~10%).
How accurate is this calculator?
The Mifflin-St Jeor equation is the most accurate general formula, typically within ±10% for healthy adults. The bigger error source is overestimating your activity level — when in doubt, pick the lower one and let 2–3 weeks of scale data correct it.
Why am I not losing weight in my calculated deficit?
Usually one of three things: portions are drifting above the target (weigh food for a week to check), activity dropped as intake dropped (step counts quietly fall in a deficit — track them), or water retention is masking fat loss. Give any change three weeks before judging it.
Does walking really change my TDEE?
Significantly. The gap between a sedentary day (multiplier 1.2) and an active one (1.55) is 500+ kcal for most adults — often more than a gym session. Everyday movement is the most underrated lever in the whole equation.
For site owners
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<iframe src="https://www.bigbeefit.com/embed/tdee-calculator" width="100%" height="560"
style="border:0;border-radius:12px" title="TDEE Calculator – How Many Calories Do You Burn a Day?"
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<p>Free <a href="https://www.bigbeefit.com/tools/tdee-calculator">TDEE Calculator – How Many Calories Do You Burn a Day?</a> by BigBeeFit</p>Free for any website — blogs, gyms, coaching sites. Please keep the attribution link so your readers can find the full tool.
Your activity level isn't a guess. Measure it.
StepDay turns Apple Health into clear daily step, workout, and sleep trends, so you know which TDEE multiplier is actually yours — free on the App Store.