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Nutrition Tools

Macro Calculator

Calculate your daily calorie needs and ideal macro targets for your goal — whether you want to lose fat, build muscle, or maintain your current weight. Enter your stats below to get a personalised estimate.

Nutrition Planner

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What Are Macronutrients?

Macronutrients — protein, carbohydrates, and fat — are the three main nutrients that supply your body with energy. Unlike micronutrients (vitamins and minerals), which are needed in small amounts, macros are consumed in large quantities every day and form the structural basis of most foods. Understanding how each macro functions helps you make better food choices and reach your health goals faster.

  • Protein (4 cal/g) — builds and repairs muscle, supports immune function, and is the most satiating macronutrient
  • Carbohydrates (4 cal/g) — the body's preferred energy source, especially for the brain and high-intensity exercise
  • Fat (9 cal/g) — essential for hormone production, fat-soluble vitamin absorption, and long-duration energy

How to Use Your Macro Targets

Once you have your macro targets, the next step is tracking what you eat against them. You do not need to hit every number perfectly every day — aim to be within 5–10% over a weekly average. Consistency across a week matters far more than precision on any single day. Most people find it easiest to plan meals in advance using a meal planner, which lets you see your macro totals before you cook rather than logging after the fact.

  • Start with protein — hit your protein target first, then fill the remaining calories with carbs and fat
  • Plan meals in advance to avoid calorie and macro surprises at the end of the day
  • Track for 2–3 weeks before adjusting — short-term weight fluctuations are often water, not fat

Macros for Different Goals

The right macro split depends on your primary goal. For fat loss, a modest calorie deficit (300–500 calories below TDEE) combined with high protein intake preserves muscle while the deficit comes from body fat. For muscle building, a small surplus (200–300 calories above TDEE) with high protein and adequate carbohydrates to fuel training is the most evidence-based approach. For general health and weight maintenance, a balanced split with sufficient protein is all most people need.

  • Fat loss: calorie deficit + high protein (1.8–2.2 g/kg) to preserve muscle
  • Muscle gain: small calorie surplus + high protein + carbs timed around training
  • Maintenance: moderate protein (1.6 g/kg) with flexible carb and fat allocation

Frequently Asked Questions

What are macros?

Macros (macronutrients) are the three main nutrient categories that provide energy: protein, carbohydrates, and fat. Every food you eat is made up of some combination of these three, measured in grams. Protein and carbohydrates each provide 4 calories per gram, while fat provides 9 calories per gram.

How does this macro calculator work?

The calculator uses your body weight, height, age, biological sex, and activity level to estimate your Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation — one of the most validated formulas in nutrition science. From your TDEE, it adjusts for your goal (lose fat, maintain, or gain muscle) and splits calories into protein, carbohydrate, and fat targets.

How much protein do I need per day?

For most active adults, a target of 1.6–2.2 g of protein per kg of body weight (0.73–1.0 g per pound) is well-supported by research. Higher protein intakes support muscle retention during a calorie deficit and muscle building during a surplus. Sedentary adults can get by with less — around 0.8 g/kg — but active people benefit from the higher end.

What macro split should I use for weight loss?

There is no single correct split, but higher-protein approaches (30–35% of calories from protein) are consistently associated with better fat loss outcomes because protein is satiating and preserves lean mass. A common starting point is 35% protein, 35% carbohydrate, 30% fat. Adjust based on how you feel after 2–3 weeks.

What is TDEE?

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a day, including your basal metabolic rate (BMR, the calories burned at rest) plus the energy used for physical activity, digestion, and daily movement. Eating at your TDEE maintains weight. Eating below it creates a deficit; eating above it creates a surplus.

How accurate is the macro calculator?

Calculators based on the Mifflin-St Jeor formula are accurate within about 10% for most people. Individual variation in metabolic rate, muscle mass, and non-exercise activity thermogenesis (NEAT) means your actual needs may differ. Use the output as a starting point, track for 2–3 weeks, and adjust if your weight is not changing as expected.