Macro Calculator

Macro Calculator

Calculate macronutrient gram targets and customized diet ratios instantly using local browser memory.

Mathematical Formula & Standards

Each macronutrient has a known caloric density, which allows percentage-to-gram conversion:

1. 1Macro Split Presets:
2. 2Balanced (40/30/30): 40% carbs, 30% protein, 30% fat — suitable for general fitness and weight maintenance.
3. 3High Protein / Low Carb (25/40/35): 25% carbs, 40% protein, 35% fat — optimised for muscle gain or fat loss with muscle preservation.
4. 4Keto (5/25/70): 5% carbs, 25% protein, 70% fat — induces ketosis for those following a very low carbohydrate protocol.

1. 2Gram Calculation Formula:

Protein (g) = (Calories * Protein % / 4)

Carbs (g) = (Calories * Carb % / 4)

Fat (g) = (Calories * Fat % / 9)

[Daily Calorie Target + Macro Split Selection]
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[Percentage allocations → gram conversion via kcal/g density]
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[Protein (g) + Carbohydrates (g) + Fat (g) daily targets]

Input Methodology

1. 1Determine Your Calorie Target: Use the Calorie Calculator to find your TDEE, then adjust for your goal (deficit, maintenance, or surplus).
2. 2Enter Daily Calories: Input your calorie target into the calculator.
3. 3Select Macro Split: Choose the ratio preset that matches your dietary framework.
4. 4Review Results: See daily gram targets for protein, carbohydrates, and fat.

Macro Calculator — Macronutrient Breakdown by Calorie Target

For a daily target of 2,000 calories under a standard 40% carb, 30% protein, and 30% fat dietary split, your body requires exactly 200g of carbohydrates, 150g of protein, and 67g of fat. This conversion relies on standard caloric densities (4 kcal/g for carbs/protein, 9 kcal/g for fat). This tool converts raw calorie targets into precise gram distributions based on your selected macro framework.

• Fat Grams Seem Too Low: This is mathematically correct. Fat has 9 kcal/g, so the gram count for a percentage-based fat allocation is always smaller than expected. Double-check the calculation manually: (Calories × Fat%) ÷ 9.
• Keto Carb Target Seems Too High: Verify your calorie input is not unreasonably large. At 3,000 kcal with a 5% carb allocation, carbs = 37.5 g, which is near the upper boundary of ketosis.
• Results Not Updating: Clear browser cache and reload.

What is the best macro ratio for fat loss?

No single macro ratio is universally optimal. Studies comparing high-protein-low-carb diets, balanced diets, and keto diets show similar long-term fat loss outcomes when total calories and protein are matched. The "best" ratio is the one you can adhere to consistently.

How does the keto macro split induce ketosis?

By restricting carbohydrates to approximately 5% of calories (typically under 50 g/day), glycogen stores deplete within 24–72 hours. The liver then shifts to producing ketone bodies from fat as an alternative fuel source for the brain and muscles.

Why does protein have 4 kcal/g if amino acids are used for muscle, not energy?

In practice, excess protein and protein not incorporated into tissue is deaminated and the carbon skeleton is used for energy or gluconeogenesis. The 4 kcal/g figure represents the average gross energy yield of protein combustion measured by bomb calorimetry.

Is my dietary data stored anywhere?

No. All calculations run client-side in your local browser.

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