🥗 Macro Calculator

Calculate daily macronutrient targets — protein, carbs, and fat in grams — from your body stats, activity level, and goal. Converts your calorie budget into a macro split.

Protein, Carbs, Fat Split for Your Goal

BrainyCalculators editorial insight — unique to this tool

Cutting often uses 40/30/30 or high-protein 40% protein; keto pushes fat to 70%+. A 2,000 kcal cut at 2 g/kg protein for 80 kg lifter = 160 g protein (640 kcal). Indian vegetarian diets need deliberate protein from dal, paneer, whey to hit grams-per-kg targets.

When to use this calculator

Use after you know total calories (from TDEE) to split macros. For protein-only target, use Protein Intake.

Just need a daily calorie target?

This page splits calories into protein, carb, and fat grams. For a single calorie number for your goal, use the Calorie Calculator →

Gender

Age (years)

Height (cm)

Weight (kg)

Activity Level

Fitness Goal

What is a Macro Calculator?

A macro calculator translates your daily calorie budget into grams of protein, carbohydrate, and fat. It derives calories from the Mifflin-St Jeor BMR and activity level, then applies goal-based ratios (e.g., higher protein for muscle gain or fat loss) to produce specific gram targets for each macronutrient.

Use this page when you already train or track food and need macro grams, not just a calorie number. Protein is set relative to body weight, fat as a percentage of calories, and carbohydrate fills the remainder — the split that drives body-composition results.

If you only need a single daily calorie figure for weight loss or gain, use the Calorie Calculator. For maintenance energy expenditure alone, use the TDEE Calculator; for resting metabolism, the BMR Calculator.

Calculation Method

Step 1 — BMR (Mifflin-St Jeor):

Male: 10×weight + 6.25×height − 5×age + 5

Female: 10×weight + 6.25×height − 5×age − 161

Step 2 — TDEE: BMR × Activity Multiplier

Step 3 — Calorie Target: TDEE × Goal Multiplier

Step 4 — Macros: Split calories by goal ratio (protein 4 kcal/g, carbs 4 kcal/g, fat 9 kcal/g)

How to Use This Calculator

1

Enter Your Stats

Provide your gender, age, height (cm), and current weight (kg) for an accurate BMR calculation.
2

Choose Activity Level

Select how active you are during a typical week. Be honest — overestimating leads to surplus calories.
3

Set Your Goal

Choose your primary goal: weight loss, maintenance, or muscle gain. Each goal uses a different calorie adjustment and macro ratio.
4

Track Your Macros

Use a food tracking app like MyFitnessPal to hit your daily protein, carb, and fat targets. Adjust after 2–4 weeks based on results.

Real-World Example

Male, 30 years, 175 cm, 80 kg, Moderately Active (×1.55), Goal: Lose Weight (−15%):

BMR = 10×80 + 6.25×175 − 5×30 + 5 = 1,904 cal

TDEE = 1,904 × 1.55 = 2,951 cal

Target = 2,951 × 0.85 = 2,508 cal

Protein (40%) = 2,508 × 0.40 / 4 = 251g

Carbs (35%) = 2,508 × 0.35 / 4 = 219g

Fat (25%) = 2,508 × 0.25 / 9 = 70g

How the Macro Calculator Works

Formula, assumptions, and calculation steps for this health tool.

Formula Used

Macro grams = (Calories * Macro Percentage) / Calories per gram

Methodology

Health calculators use published screening formulas and common planning rules to estimate body, nutrition, pregnancy, or fitness metrics from user inputs.

Calculation Steps

Enter the personal measurements requested by the tool.
Convert height, weight, age, dates, or activity inputs to standard units.
Apply the health or fitness formula for the selected metric.
Show the estimate with practical ranges or interpretation where available.

Assumptions and Limits

Results are educational estimates, not diagnosis or medical advice.
Individual factors such as medication, pregnancy, and medical history can change interpretation.
Consult a clinician for personal health decisions.

Reference basis: Common public-health and sports-science screening formulas.

Frequently Asked Questions

What are macros (macronutrients)?

Macronutrients are the three main nutrients your body uses for energy: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Protein supports muscle building and repair, carbs provide quick energy, and fats support hormones, brain function, and nutrient absorption.

What does IIFYM mean?

IIFYM stands for If It Fits Your Macros. It is a flexible dieting approach where you can eat any food as long as your daily macro targets are met. It focuses on total macronutrient intake rather than meal timing or specific foods, making it easier to maintain long-term.

How do I track my macros?

Use a food tracking app such as MyFitnessPal, Cronometer, or Lose It!. Log every meal and snack using the barcode scanner or food database. Weigh food with a kitchen scale for accuracy. After 2–4 weeks, adjust targets based on actual progress — if weight is not moving, adjust calories by 100–200 per day.

Should I prioritise carbs or fat for energy?

Both carbohydrates and fat are effective energy sources. Carbs are the body's preferred fuel for high-intensity exercise (Zone 3–5). Fat is the primary fuel at rest and during low-intensity activity. For most people following a mixed diet, carbohydrates are prioritised around workouts and fat fills the remaining calorie budget. Neither is inherently superior — total calorie balance and protein intake matter most.

Real-World Applications

🏋️

Fat Loss Programme

Calculate TDEE and apply a 500 kcal deficit, then set protein high (2.0 g/kg LBM) to preserve muscle during the cut — with carbs and fat filling the remaining calories.

💪

Muscle Building (Bulk)

Set a 200–300 kcal surplus over TDEE with protein at 1.8–2.2 g/kg body weight to maximise muscle protein synthesis without excessive fat gain.

🏃

Endurance Athlete Fuelling

Adjust carbohydrate targets upward (5–7 g/kg on training days, 3–5 g/kg on rest days) for marathon, triathlon, or cycling training to fuel performance and replenish glycogen.

🩺

Diabetic Diet Planning

Calculate daily carbohydrate gram targets for type 2 diabetics — typically 100–150 g/day for moderate low-carb — to improve glycaemic control alongside medical supervision.

🥗

Meal Prep Planning

Use daily macro targets to design a meal plan and grocery list — distributing protein, carbs, and fat across meals to hit targets without tracking every individual item.

📊

Body Recomposition

Set calories at or slightly above TDEE maintenance with high protein (2.2–2.6 g/kg) and resistance training to simultaneously lose fat and gain muscle — the "recomp" approach.

Common Mistakes

Overestimating activity level in TDEE calculation

Selecting "Very Active" when you train 3× per week results in TDEE overestimation by 300–500 kcal/day — leading to a calorie "deficit" that is actually maintenance or a surplus. Use "Moderately Active" for most gym-goers.

Setting protein too low during fat loss

Inadequate protein (below 1.6 g/kg) during a calorie deficit leads to muscle loss alongside fat loss — reducing metabolic rate and making it harder to maintain the deficit. Prioritise protein above all other macros when cutting.

Applying the same macro split regardless of goal

A standard "40/40/20" macro split (carb/protein/fat) is arbitrary and not evidence-based for any specific goal. Protein and calorie totals should be set first based on goal; carbs and fat are then allocated from the remaining calories.

Not adjusting macros as body weight changes

TDEE and protein targets are based on body weight and composition — which change as you lose fat or gain muscle. Recalculate macros every 4–6 weeks or when weight changes by more than 5 kg to maintain appropriate targets.

Treating calculated macros as mandatory to hit exactly

Macro targets are daily goals, not rigid requirements. Being within ±5g of protein and ±10g of carbs/fat each day is effectively identical to hitting exact targets. Obsessive exact tracking is unsustainable and unnecessary.

Macro Split Reference by Goal

Goal	Protein	Carbs	Fat
Fat Loss	30–40%	30–40%	20–30%
Muscle Gain	25–35%	40–50%	20–25%
Maintenance	20–30%	40–50%	25–35%
Endurance	15–20%	55–65%	20–25%
Low-Carb / Keto	25–35%	5–10%	55–70%
General Health	15–25%	45–55%	25–35%

References

Morton, R.W. et al. "A Systematic Review, Meta-analysis and Meta-regression of the Effect of Protein Supplementation on Resistance Training–induced Gains in Muscle Mass and Strength." British Journal of Sports Medicine, 2018.
Mifflin, M.D. et al. "A New Predictive Equation for Resting Energy Expenditure in Healthy Individuals." American Journal of Clinical Nutrition, 1990.
Thomas, D.T. et al. "American College of Sports Medicine Joint Position Statement: Nutrition and Athletic Performance." Medicine & Science in Sports & Exercise, 2016.
Hall, K.D. et al. "Calorie for Calorie, Dietary Fat Restriction Results in More Body Fat Loss than Carbohydrate Restriction in People with Obesity." Cell Metabolism, 2015.
Helms, E.R. et al. "A Systematic Review of Dietary Protein During Caloric Restriction in Resistance Trained Lean Athletes." International Journal of Sport Nutrition, 2014.