OnSumoTools

Macronutrient Calculator (2026)

This macro calculator converts your daily calorie target into specific protein, carbohydrate, and fat amounts in grams. Enter your goal, whether fat loss, muscle gain, or maintenance, and it splits your calories across the three macronutrients. The ratios are set by your inputs, not generic defaults.

Your daily protein, carbs, and fat targets in seconds.

Unit system

Daily calories

2,507 kcal

TDEE: 2,507 kcal

BMR

1,618 kcal

Goal

Maintain

Balanced

Daily macro targets

Protein (30%)

188 g

752 kcal

Carbs (40%)

251 g

1,003 kcal

Fat (30%)

84 g

752 kcal

Per-meal breakdown (3 meals/day)

Protein

63 g

Carbs

84 g

Fat

28 g

Preset comparison

DietProteinCarbsFat
Balanced188 g251 g84 g
High-protein251 g188 g84 g
Low-carb219 g157 g111 g
Keto157 g31 g195 g

Macro targets are estimates based on population-level formulas. Individual needs vary with genetics, training intensity, and health conditions. Track weight and energy for 2–4 weeks and adjust. Not medical or dietary advice.

How does the Macronutrient Calculator work step by step?

This tool calculates your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation: BMR = (10 × weight_kg) + (6.25 × height_cm) − (5 × age) + 5 (men) or −161 (women). BMR is then multiplied by an activity factor (sedentary 1.2, lightly active 1.375, moderately active 1.55, very active 1.725, extra active 1.9) to produce your Total Daily Energy Expenditure (TDEE). A goal adjustment is applied: −500 kcal/day for weight loss, +250 kcal/day for muscle gain, or no change for maintenance. The adjusted calories are then split into protein, carbohydrate, and fat targets using your chosen diet ratios. Protein and carbs provide 4 kcal per gram; fat provides 9 kcal per gram. The tool includes four built-in ratio presets (Balanced 30/40/30, High-protein 40/30/30, Low-carb 35/25/40, Keto 25/5/70) and a custom mode where you define your own percentages.

What does a typical Macronutrient Calculator result look like?

A 30-year-old man weighing 80 kg at 170 cm with moderate activity and a maintenance goal has a BMR of about 1,718 kcal and a TDEE of about 2,662 kcal. Using the Balanced preset (30% protein, 40% carbs, 30% fat), daily targets would be roughly 200 g protein, 266 g carbs, and 89 g fat. Splitting across 3 meals gives about 67 g protein, 89 g carbs, and 30 g fat per meal.

Frequently asked questions

  • What are macronutrients?

    Macronutrients are the three main calorie-providing nutrients: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Every calorie you eat comes from one of these three sources.

  • How much protein do I need per day?

    For most active people, 0.7-1.0 grams of protein per pound of bodyweight (1.5-2.2g/kg) is a validated range for muscle maintenance and growth. Sedentary adults need less, around 0.36g per pound (0.8g/kg).

  • What is the difference between macros for weight loss and muscle gain?

    Weight loss macros are calculated from a calorie deficit; muscle-gain macros from a surplus. The macro ratios can be similar, but total grams differ because the calorie bases are different. Higher protein is recommended in both cases to preserve muscle.

  • What happens if I eat too little fat?

    Fat is required for absorbing fat-soluble vitamins (A, D, E, K) and for hormone production. Going below 20% of calories from fat for extended periods can impair these functions. Most nutrition guidelines set a minimum of 0.3-0.5g of fat per pound of bodyweight.

Related tools

Calories are the budget, macros are the split

Macronutrients are protein, carbohydrates and fat. They're the three nutrients that supply calories. Protein and carbs give 4 calories per gram. Fat gives 9. Once you know your calorie target, the next question is how to divide it.

Enter your body stats and goal and the calculator returns daily grams of protein, carbs and fat. Use it as a starting plan.

How much protein

The minimum to avoid deficiency is low, around 0.8 grams per kilogram of body weight. Active people and people trying to build muscle or keep it while dieting generally do better with more. Many coaches suggest somewhere between 1.4 and 2.2 grams per kilogram.

Protein is filling and helps preserve muscle in a deficit. It's usually the first macro to set.

Fat and carbs fill the rest

Fat is needed for hormones and for absorbing vitamins A, D, E and K. Don't drop it too low. Going too far under, below about 20 percent of calories for a long stretch, can cause problems with hormones and energy. A range of 20 to 35 percent of calories works for most people.

Carbs take what's left. They're your main fuel for hard training. Endurance athletes and people who lift heavily often do better with more of them. Someone with a desk job and a gentle walking routine can run fewer.

Fat loss versus muscle gain

For fat loss, keep protein high, keep fat sensible, and trim carbs a bit to create the deficit. For muscle gain, add a modest calorie surplus and let carbs rise, because they power training and recovery. Protein stays about the same in both.

Those are starting points. Adjust over a few weeks based on your energy, training and the scale trend.

Don't obsess

Hitting numbers to the gram isn't needed. Being near your protein goal and calorie target most days matters more than perfect macros every day. Choose whole foods most of the time, and keep it something you can stick to.

This tool provides general guidance and isn't medical advice. People with kidney disease, diabetes or other conditions should get a plan from a professional. Your data stays in your browser.