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Calorie Calculator

Use this adult calorie calculator to estimate maintenance calories, TDEE, BMR, goal calories, calorie deficit or surplus, and basic macro targets.

Calorie Calculator

Sex
Maintenance calories
2,668 kcal/day
BMR 1,721 kcal/day
Formula Mifflin-St Jeor
Activity Moderately active (1.55)
Goal calories 2,668 kcal/day
Deficit / surplus No change
GoalCaloriesChange
Mild weight loss2,418 kcal/day-250 kcal/day
Weight loss2,168 kcal/day-500 kcal/day
Maintain weight2,668 kcal/dayNo change
Lean weight gain2,918 kcal/day+250 kcal/day
Faster weight gain3,168 kcal/day+500 kcal/day
Macro targets
Protein 136 g
Fat 74 g
Carbs 364 g

Based on 0.8 g protein per lb, fat at 25% of selected calories, and carbs from remaining calories.

This calorie calculator is for adult educational estimates only. It is not medical advice and is not for pregnancy, eating disorders, pediatric needs, clinical nutrition plans, or emergency weight changes.

How it works

Formula and steps

The formula shows how the calorie calculator turns your inputs into the result. Use it to check the calculation, then follow the example steps to see each part of the math.

Formula & steps

Mifflin-St Jeor BMR formula

BMR = 10W + 6.25H - 5A + S

Use this default adult BMR estimate when body fat percentage is not entered.

BMR= Basal metabolic rate in calories per day
W= Weight in kilograms
H= Height in centimeters
A= Age in years
S= +5 for male, -161 for female

Katch-McArdle BMR formula

BMR = 370 + 21.6 x lean mass kg

Use this optional formula when body fat percentage is entered and lean mass can be estimated.

BMR= Basal metabolic rate in calories per day
lean mass kg= Weight in kilograms x (1 - body fat percentage / 100)

TDEE formula

TDEE = BMR x activity multiplier

Use this to estimate maintenance calories after choosing an activity level.

TDEE= Total daily energy expenditure, or maintenance calories
BMR= Basal metabolic rate
activity multiplier= Sedentary 1.2 through extra active 1.9

Goal calories formula

goal calories = TDEE + deficit or surplus

Use this to estimate calorie targets for losing, maintaining, or gaining weight.

goal calories= Estimated daily calorie target
deficit= A negative adjustment such as -250 or -500 kcal/day
surplus= A positive adjustment such as +250 or +500 kcal/day
  1. 1Enter sex, age, height, weight, activity level, and a goal.
  2. 2Use Mifflin-St Jeor by default, or Katch-McArdle when body fat percentage is entered.
  3. 3Multiply BMR by the selected activity multiplier to estimate TDEE and maintenance calories.
  4. 4Apply the selected calorie deficit or surplus to estimate daily goal calories.
  5. 5Estimate macros from the selected goal calories using protein at 0.8 g per lb, fat at 25% of calories, and carbs from remaining calories.

Worked examples

A 30-year-old male at 5 ft 9 in, 170 lb, and moderate activity has estimated TDEE near 2,600 kcal/day.

A 35-year-old female at 165 cm, 65 kg, and light activity has estimated maintenance calories near 1,850 kcal/day.

Choosing weight loss subtracts about 500 kcal/day from estimated TDEE, while lean weight gain adds about 250 kcal/day.

Common uses

  • TDEE calculator
  • Daily calorie calculator
  • Maintenance calories
  • Calorie deficit calculator
  • BMR calculator
  • Basic macro targets

Common mistakes

  • Treating TDEE as exact instead of an estimate that should be adjusted using real weight trends.
  • Choosing an activity level that reflects a best week instead of a normal week.
  • Using body fat percentage from an unreliable estimate and assuming Katch-McArdle is automatically more accurate.
  • Using very low calorie targets without medical supervision.

Calorie guide

How to use the calorie calculator

This adult calorie calculator estimates maintenance calories, TDEE, BMR, goal calories, and basic macro targets from the numbers you enter. Enter your normal adult stats, choose the activity level that best matches a typical week, and select a goal.

Body fat percentage is optional. Leave it blank to use Mifflin-St Jeor. Enter it only when you have a reasonable estimate and want the calculator to use Katch-McArdle based on estimated lean mass.

TDEE (Total Daily Energy Expenditure) vs BMR (Basal Metabolic Rate)

BMR estimates calories used at rest for basic body functions. TDEE estimates total daily calories by multiplying BMR by an activity factor. For most calorie planning, TDEE is the maintenance-calorie estimate because it includes daily movement and exercise.

Calorie goals

Maintenance keeps the target near estimated TDEE. Mild loss subtracts 250 kcal/day, weight loss subtracts 500 kcal/day, lean gain adds 250 kcal/day, and faster gain adds 500 kcal/day. Targets below 1,000 kcal/day are flagged instead of presented as a recommendation.

Activity multiplier table

Activity levelMultiplierTypical use
Sedentary1.20 workouts per week.
Lightly active1.375About 1 to 3 workouts per week.
Moderately active1.55About 3 to 5 workouts per week.
Very active1.725About 6 to 7 workouts per week.
Extra active1.97+ workouts per week or a physically demanding job.

Macro target explanation

The macro targets are simple educational defaults: protein at 0.8 grams per pound of body weight, fat at 25% of selected goal calories, and carbohydrates from the remaining calories. They are not a personalized nutrition plan.

Accuracy and limitations

TDEE formulas are estimates. Real needs can change with medication, metabolic adaptation, training, illness, sleep, stress, food tracking error, and daily movement. Use the result as a starting point and adjust based on several weeks of body-weight and intake trends.

FAQ