Home
Back
James Smith Macro Equations:
BMR (men) = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)
BMR (women) = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)
TDEE = BMR × activity multiplier
Calories = TDEE - deficit
Protein (g) = 1.6 × weight
Fat (g) = 0.8 × weight
Carbs (g) = (calories - protein × 4 - fat × 9) / 4
| From: | To: |
The James Smith Macro Calculator uses the Harris-Benedict equation to calculate Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE), then determines optimal macronutrient distribution for weight management goals.
The calculator uses the following equations:
BMR (men) = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)
BMR (women) = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)
TDEE = BMR × activity multiplier
Calories = TDEE - deficit
Protein (g) = 1.6 × weight
Fat (g) = 0.8 × weight
Carbs (g) = (calories - protein × 4 - fat × 9) / 4
Explanation: The equations account for individual metabolic rate, activity level, and weight management goals to provide personalized macronutrient targets.
Details: Proper macro calculation is essential for effective weight management, muscle preservation during weight loss, and optimal athletic performance.
Tips: Enter accurate weight in kg, height in cm, age in years, select appropriate activity level, and specify your desired calorie deficit for weight loss goals.
Q1: What is the difference between BMR and TDEE?
A: BMR (Basal Metabolic Rate) is the calories your body needs at complete rest, while TDEE (Total Daily Energy Expenditure) includes all daily activities and exercise.
Q2: How accurate is the Harris-Benedict equation?
A: It provides a good estimate for most people, but individual variations exist. For precise measurements, metabolic testing is recommended.
Q3: What activity multiplier should I choose?
A: Select based on your daily activity: Sedentary (office job), Light (light exercise 1-3 days/week), Moderate (moderate exercise 3-5 days/week), Very Active (hard exercise 6-7 days/week), Extra Active (very hard exercise and physical job).
Q4: How much calorie deficit should I use for weight loss?
A: A deficit of 300-500 kcal/day typically results in sustainable weight loss of 0.5-1 kg per week.
Q5: Why 1.6g protein per kg of body weight?
A: This amount supports muscle preservation during weight loss and promotes satiety, which is higher than the RDA but supported by research for active individuals.