Precision Utility
Macro
Calculator
Method
TDEE Based
Approach
Flexible Dieting
Work out your daily protein, carbohydrate and fat targets in seconds. Enter your age, height, weight, activity level and goal — the calculator does the rest. You'll see a personalised macro split based on your Total Daily Energy Expenditure (TDEE), ready for flexible dieting or structured meal planning.
Body Parameters
Your Daily Target
2,325 kcal
Protein
150 g
Carbs
246 g
Fat
65 g
Calories
2,325
How the macro calculator works
Start by entering your age, height, weight and sex. The calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest.
Next, select your activity level. The calculator multiplies your BMR by an activity factor (ranging from 1.2 for sedentary to 1.9 for extra active) to give your Total Daily Energy Expenditure (TDEE) — the total calories you burn in a typical day.
Choose your goal and the calculator adjusts your calorie target accordingly: a 500 kcal deficit for weight loss, maintenance calories to hold steady, or a 500 kcal surplus for muscle gain.
Finally, your calorie target is split into macronutrients. Protein is set at 2 g per kg of bodyweight to support muscle. Fat is set at around 28% of total calories for hormone health. The remaining calories are allocated to carbohydrates for energy.
What you need to know about macronutrients
Macronutrients are the three energy-providing nutrients your body needs in large amounts every day. Each plays a distinct role:
- Protein (4 kcal per gram) — builds and repairs muscle tissue, supports immune function and produces enzymes and hormones. Aim for 1.6–2.2 g per kg of bodyweight if you train regularly
- Carbohydrates (4 kcal per gram) — your body's preferred energy source, especially during high-intensity exercise. Found in grains, fruits, vegetables and legumes
- Fat (9 kcal per gram) — essential for hormone production, brain function and absorbing fat-soluble vitamins (A, D, E, K). Include healthy sources like olive oil, nuts, avocado and oily fish
Recommended macro splits vary by goal. A common starting point is 30% protein, 40% carbohydrates and 30% fat — but individual needs depend on body composition, training style and personal preference.
Flexible dieting (also known as IIFYM — If It Fits Your Macros) means you can eat any foods you enjoy as long as you hit your daily macro targets. This approach removes the need to label foods as "good" or "bad" and makes your diet more sustainable long-term. The key is consistency with your overall intake, not perfection at every meal.
Use these targets as a starting point. Track your intake for two to three weeks, monitor your weight and energy levels, and adjust by 5–10% if progress stalls.
Frequently asked questions
What are macronutrients?
Macronutrients are the three main nutrients your body needs in large amounts: protein, carbohydrates and fat. Each provides energy (calories) and plays a different role in bodily functions, muscle repair, brain function and hormone production.
How does the macro calculator work?
The calculator estimates your Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation for BMR, multiplied by your activity level. It then splits your calorie target into protein (1.6–2.0 g per kg bodyweight), fat (around 28% of calories) and carbohydrates (the remainder).
How much protein do I need per day?
For most active adults, 1.6 to 2.2 grams of protein per kilogram of bodyweight is recommended. This supports muscle repair, recovery and lean mass retention whether you're losing weight or building muscle.
Should I track macros or just calories?
Tracking macros gives you more control over body composition than calories alone. Two diets with the same calories can produce very different results depending on the protein, carb and fat split. Macro tracking is especially useful for muscle gain, fat loss or athletic performance.
What is flexible dieting (IIFYM)?
Flexible dieting, also called If It Fits Your Macros (IIFYM), means you can eat any foods you like as long as you hit your daily protein, carb and fat targets. It focuses on overall nutrient balance rather than labelling foods as "good" or "bad".
How do I adjust macros for weight loss vs muscle gain?
For weight loss, reduce your TDEE by 300–500 kcal while keeping protein high to preserve muscle. For muscle gain, add 250–500 kcal above TDEE with adequate protein. The calculator adjusts your targets automatically based on the goal you select.