Estimate your daily energy needs. Calculate resting calories and total daily energy expenditure, then explore a calorie adjustment for maintenance, loss or gain. Choose activity based on your actual routine rather than assuming everyone is moderately active.
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Inputs
For adults 18 and older. Not for pregnancy, breastfeeding, eating disorder care or medically prescribed nutrition.
Enter your details. If you know body fat %, we’ll use Katch-McArdle; otherwise Mifflin-St Jeor.
Goal
Results
Enter your details, then calculate.
Tips
- A body fat estimate can introduce additional error. Katch McArdle is an alternative, not automatically a more accurate result.
- Re-estimate if your weight changes ±2–3% or activity shifts.
- Avoid extreme deficits/surpluses if you have medical conditions—consult your physician.
How to use this calculator
- Confirm this general adult calculator fits your situation.
- Enter age, height and weight. Imperial height is total inches; 6 feet 7 inches is 79 inches.
- Leave body fat blank unless you have a reliable estimate.
- Choose your typical activity level and goal. Adjustments are calories per day, not promised rates of weight change.
- Calculate again after changing any input. Copy Results copies only a current calculation.
What the numbers mean
BMR / resting estimate: Estimated energy used at rest. Mifflin St Jeor technically predicts resting energy expenditure.
TDEE: Resting estimate multiplied by an activity assumption to approximate daily maintenance.
Daily calories: Maintenance plus or minus your selected adjustment. This is not an individualized prescription.
The Mifflin St Jeor equation is 10 × kilograms + 6.25 × centimetres minus 5 × age, then +5 for the male equation or minus 161 for the female equation. The optional Katch McArdle method is 370 + 21.6 × estimated lean mass in kilograms. The page retains both existing methods; entering body fat selects the latter.
Mifflin St Jeor original research · NIDDK Body Weight Planner and eligibility guidance
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Calorie calculator FAQs
Tap a question to reveal its answer.
How do I choose my activity level?
Consider work, walking, household tasks and training across your usual week. Exercise frequency alone is a rough guide. Do not automatically choose moderate activity or add workout calories again after selecting a factor that already includes training.
Is a 500 calorie deficit right for everyone?
No. A fixed deficit affects a smaller maintenance estimate more strongly. The calculator flags a deficit above 25% and withholds targets below 1,000 kcal/day; these are guardrails, not proof that other targets are appropriate. Seek individual guidance for medical needs.
Will this predict exactly how much weight I lose each week?
No. Water, digestion, adherence and changing energy needs affect scale weight. A calorie adjustment is not a guaranteed weekly loss or gain.
Is a body fat based formula always better?
No. An inaccurate body fat estimate can make the result less useful. Leave body fat blank if you do not have a reliable estimate; the calculator will use Mifflin St Jeor.
How should I use the estimate?
Treat it as a starting estimate, not a prescription. Compare your average intake, weight trend, energy and training recovery over several weeks before deciding whether an adjustment makes sense.
Do I need different targets on rest days?
Not necessarily. The activity factor estimates an average day across your routine. Consistency may be simpler than changing targets every day. A coach can help plan variations when useful.
Are BMR and resting energy expenditure identical?
Strictly, no. Mifflin St Jeor predicts resting energy expenditure. BMR is commonly used as shorthand in calculators, but the testing conditions differ. Neither number is your full daily food requirement.