IIFYM Macro Calculator

IIFYM Formulas:

\[ BMR = 655.1 + (9.563 \times W) + (1.850 \times H) - (4.676 \times A) \] \[ TDEE = BMR \times AF \] \[ DC = TDEE - 500 \] \[ P = (DC \times 0.25) / 4 \] \[ C = (DC \times 0.55) / 4 \] \[ F = (DC \times 0.20) / 9 \]

Weight:

Height:

Age:

years

Activity Factor:

BMR:

TDEE:

Daily Calories (Deficit):

Protein:

Carbohydrates:

Fat:

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1. What is IIFYM?

IIFYM (If It Fits Your Macros) is a flexible dieting approach that focuses on meeting daily macronutrient targets rather than restricting specific foods. This calculator helps determine your personalized macronutrient needs based on your body metrics and activity level.

2. How Does the Calculator Work?

The calculator uses the following formulas:

Where:

\( W \) — Weight in kilograms
\( H \) — Height in centimeters
\( A \) — Age in years
\( AF \) — Activity factor (1.2 to 1.9)
\( BMR \) — Basal Metabolic Rate (kcal/day)
\( TDEE \) — Total Daily Energy Expenditure (kcal/day)
\( DC \) — Daily Calories with 500 kcal deficit
\( P \) — Protein in grams
\( C \) — Carbohydrates in grams
\( F \) — Fat in grams

Explanation: The calculator first estimates your BMR (calories burned at rest), then adjusts for activity level to get TDEE, creates a 500 kcal deficit for weight loss, and finally splits these calories into macronutrients.

3. Importance of Macronutrient Calculation

Details: Proper macronutrient balance is essential for weight management, muscle preservation, and overall health. This calculator provides a starting point for flexible dieting while ensuring adequate protein intake.

4. Using the Calculator

Tips: Enter your weight in kg, height in cm, age in years, and select your activity level. For accurate results, measure your weight in the morning after using the bathroom.

5. Frequently Asked Questions (FAQ)

Q1: Why a 500 kcal deficit?
A: A 500 kcal daily deficit typically results in about 0.5 kg (1 lb) of weight loss per week, which is considered safe and sustainable.

Q2: Can I adjust the macro ratios?
A: Yes, the standard is 25% protein, 55% carbs, 20% fat, but these can be adjusted based on personal preference and goals.

Q3: How accurate is the BMR calculation?
A: The Harris-Benedict equation provides a good estimate, but individual variations exist. Consider professional testing for precise measurements.

Q4: What if I'm male?
A: This calculator uses the female BMR equation. For males, the equation would be: BMR = 66.5 + (13.75 × W) + (5.003 × H) - (6.755 × A).

Q5: How often should I recalculate my macros?
A: Recalculate every 4-6 weeks or after significant weight changes (±5 kg).