Macro Calculator
Estimate daily calories, BMR, TDEE, and protein, carbohydrate, and fat targets based on your body details, activity level, and goal.
Results
This calculator gives an estimate only. Actual calorie and macro needs can vary based on metabolism, training style, body composition, medical conditions, and dietary preferences. For medical or clinical nutrition advice, consult a qualified professional.
Use this Macro Calculator to estimate basal metabolic rate (BMR), total daily energy expenditure (TDEE), target calories, and daily protein, carbohydrate, and fat targets based on your body measurements, activity level, goal, and selected macro split.
Important: Calorie and macronutrient results are estimates. Actual needs can differ because of metabolism, body composition, training, health, medications, sleep, pregnancy, breastfeeding, and other factors.
BMR Calculation
The calculator uses the Mifflin–St Jeor equation.
Male:
BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) + 5
Female:
BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) − 161
BMR estimates resting energy expenditure before normal activity and exercise are added.
TDEE and Goal Calories
The calculator estimates daily maintenance calories using:
TDEE = BMR × activity factor
It then applies the selected weight-management goal:
Target calories = TDEE × (1 + goal adjustment)
A deficit uses a negative adjustment, while a surplus uses a positive adjustment. Activity multipliers and goal adjustments are planning assumptions rather than precise measurements of individual energy expenditure.
Macro Calculation
After target calories are calculated, calories are distributed according to the selected macro percentages.
Protein grams = protein calorie percentage × target calories ÷ 4
Carbohydrate grams = carbohydrate calorie percentage × target calories ÷ 4
Fat grams = fat calorie percentage × target calories ÷ 9
Protein and carbohydrate provide approximately 4 kcal per gram, while fat provides approximately 9 kcal per gram.
Worked Example
Suppose a 30-year-old male weighs 180 lb, is 70 inches tall, selects moderate activity, maintenance calories, and a macro split of 30% protein, 40% carbohydrate, and 30% fat.
Converted measurements are approximately 81.65 kg and 177.8 cm.
BMR ≈ 1,783 kcal/day
Using an activity factor of 1.55:
TDEE ≈ 1,783 × 1.55 ≈ 2,763 kcal/day
At maintenance calories:
Protein ≈ 2,763 × 30% ÷ 4 ≈ 207 g/day
Carbohydrate ≈ 2,763 × 40% ÷ 4 ≈ 276 g/day
Fat ≈ 2,763 × 30% ÷ 9 ≈ 92 g/day
Important Notes
- BMR and TDEE equations estimate average energy needs and can differ from actual expenditure.
- Activity multipliers depend on how accurately your selected activity level represents daily movement and training.
- Short-term body-weight changes can reflect water, glycogen, food mass, and other factors rather than only body fat.
- For adults, established Acceptable Macronutrient Distribution Ranges are generally 45–65% of energy from carbohydrate, 20–35% from fat, and 10–35% from protein.
- A calculator preset outside these ranges may be appropriate in some specialized situations but should not automatically be treated as a general health recommendation.
- Children, adolescents, pregnant or breastfeeding people, people with eating-disorder concerns, and those with medical nutrition needs require more individualized guidance.