iKalva

Macro Calculator for Weight Loss

Calculate your personalized macros for weight loss: protein, carbs and fat with optimal caloric deficit.

kg

What macros do you need to lose weight?

Losing weight is not just about creating a calorie deficit: macronutrient distribution determines what type of tissue you lose. A high-protein diet (1.8–2.2 g/kg/day) preserves muscle mass while the deficit draws mainly from fat stores [¹]. Carbohydrates sustain training performance and prevent fatigue, while fats regulate hormones. The recommended ratio for fat loss is: 30–35% protein / 35–40% carbohydrates / 25–30% fat [²].

How to use this calculator

Select the 'Weight loss' goal and 'High' protein. Enter your weight, age, height and activity level. The calculator applies a ~500 kcal deficit over your TDEE and distributes macros prioritising protein. Adjust results if you strength train (more protein) or are very active (more carbohydrates).

Macro distribution by deficit level

Deficit typekcal/day deficitProteinCarbohydratesFat
Mild (recomposition)~200 kcal2.0 g/kg40%30%
Moderate (optimal)~400–500 kcal2.2 g/kg35%28%
Aggressive (muscle risk)>700 kcal2.4+ g/kg30%25%

FAQ

1

How much protein do I need to avoid losing muscle?

Between 1.8 and 2.2 g per kg of bodyweight per day. In aggressive caloric deficits, going up to 2.4 g/kg can minimise lean mass loss [¹].

2

Should I cut carbs to lose fat?

No. Eliminating carbs accelerates initial weight loss (water and glycogen) but does not improve fat loss long-term compared to an equivalent deficit with carbs [²]. Carbs also improve training performance, which helps preserve muscle.

3

How fast should I lose weight?

0.5–1% of bodyweight per week is the optimal range for muscle preservation. Faster increases muscle catabolism; slower is equally valid but requires more patience [³].