Macro Calculator

What is Macro Calculator?

A Macro Calculator determines how many grams of protein, carbohydrates, and fat you should consume each day based on your calorie target and dietary preferences. Calories tell you how much to eat; macros tell you what those calories are made of — two meal plans with identical calories can produce very different results for muscle, performance, and hunger.

This calculator offers two ways to set your calorie target. The Auto (TDEE) tab estimates your Total Daily Energy Expenditure with the Mifflin-St Jeor equation, then adjusts it by 500 kcal to lose or gain weight. The Manual Calories tab accepts a target you already have — for example from our TDEE calculator or calorie calculator. You then pick one of four diet templates — Balanced (30/35/35), Low Carb (20/40/40), High Protein (40/30/30), or Keto (10/20/70) — where the numbers are the percentage of calories from protein, carbs, and fat.

How to Use

1. Choose Auto (TDEE) to calculate from your stats, or Manual Calories to enter your own target.
2. Select your goal (lose, maintain, or gain weight) and preferred diet template.
3. Optionally enter how many meals you eat per day for a per-meal breakdown.
4. Click Calculate Macros to see your daily protein, carbs, and fat targets.

The 4/4/9 Rule: Converting Calories to Grams

Each macronutrient supplies a fixed amount of energy per gram: protein provides 4 kcal, carbohydrates provide 4 kcal, and fat provides 9 kcal. Once you know your daily calories and each macro's percentage share, converting to grams takes a single division:

Grams = (Daily calories x Share %) / Calories per gram

• Daily calories = your total energy target in kcal (TDEE adjusted for your goal)
• Share % = the fraction of calories assigned to that macro, e.g. 40% = 0.40
• Calories per gram = 4 for protein, 4 for carbohydrates, 9 for fat

Worked Example

Suppose your daily target is 2,200 kcal and you select the High Protein template (40% protein, 30% carbs, 30% fat):

• Protein: (2,200 x 0.40) / 4 = 220 g
• Carbs: (2,200 x 0.30) / 4 = 165 g
• Fat: (2,200 x 0.30) / 9 = 73.3 g, rounded to 73 g

Check the math: 220 x 4 + 165 x 4 + 73 x 9 = 880 + 660 + 657 = 2,197 kcal — within rounding of the target, and exactly what the calculator returns. With 3 meals per day, the per-meal breakdown shows 73.3 g protein, 55.0 g carbs, and 24.3 g fat.

In Auto mode, a 30-year-old male (180 cm, 80 kg, moderately active) gets a TDEE of 2,759 kcal — 207 g protein, 241 g carbs, and 107 g fat on the Balanced template. Lose Weight drops the target to 2,259 kcal; Gain Weight raises it to 3,259 kcal.

Macro Targets by Calorie Level

Gram targets for all four templates at common calorie levels, computed with the calculator's 4/4/9 conversion and rounding.

Setting Protein First

If your goal involves building or keeping muscle, set protein first. Research on resistance-trained adults supports 1.6–2.2 grams per kilogram of body weight per day (about 0.7–1.0 g per pound) for maximizing muscle growth and retention — for an 80 kg (176 lb) person, roughly 128–176 g daily (512–704 kcal). Then allocate 20–35% of calories to fat for hormone production, and fill the rest with carbohydrates to fuel training.

Adjusting Macros for Cutting vs Bulking

This calculator adjusts calories by 500 kcal per day for goal-based changes: minus 500 to lose weight, plus 500 to gain. Since a pound of body fat stores roughly 3,500 kcal, that is about 0.45 kg (1 lb) of change per week — a sustainable pace.

When cutting, keep protein near the high end of your range (closer to 2.2 g/kg) to protect muscle, and take most of the reduction from carbs and fat. When bulking, keep the surplus modest and add calories mainly from carbs around workouts. Recalculate every four to six weeks, since your TDEE shifts as your weight changes.

Tips for Tracking Your Macros

• Weigh food with a kitchen scale in grams, logging it raw when possible — cooking changes weight but not macro content.
• Log cooking oils, sauces, drinks, and snacks; they are the most commonly missed calories.
• Aim within 5–10 g of each daily target; weekly averages matter more than any single day.
• Use the per-meal breakdown above to spread protein evenly across the day.

Frequently Asked Questions