Macro Calculator
Trying to hit protein, carbs, and fat targets? Enter your calories and split and you will get grams for each macro. It makes meal planning easier.
TL;DR
- Total calories set whether you gain or lose weight
- Macronutrient Energy Density Constants: Target Grams = (Total Daily Calories × Macro Percentage) ÷ Energy Density Consta
- Example: 2,000 kcal Target for Fat Loss with High-Protein Partitioning
How it works
Total calories set whether you gain or lose weight. The macro split decides if that weight is mostly muscle or fat.
The math
Set your TDEE, adjust for goal, then split calories into grams using 4 cal/g for protein and carbs and 9 cal/g for fat.
1 gram of Protein = 4 calories, 1 gram of Carbohydrate = 4 calories, and 1 gram of Fat = 9 calories. For instance, allocating 600 calories to protein yields 600 ÷ 4 = 150g of protein.
Examples
Example: 2,000 kcal Target for Fat Loss with High-Protein Partitioning
- Establish daily energy intake target: 2,000 kcal
- Select target macro ratio: 40% Carbohydrates, 30% Protein, 30% Fats
- Calculate Carbohydrates: (2,000 × 0.40) = 800 kcal ÷ 4 kcal/g = 200g Carbs
- Calculate Protein: (2,000 × 0.30) = 600 kcal ÷ 4 kcal/g = 150g Protein
- Calculate Fat: (2,000 × 0.30) = 600 kcal ÷ 9 kcal/g = 66.7g Fat
- Daily Target: 150g Protein, 200g Carbs, 67g Fat.
When to use it
✦ Fat Loss & Body Recomposition
Elevating protein intake (1.8g to 2.2g per kg of body weight) prevents lean muscle loss during calorie deficits.
✦ Endurance & Resistance Athletic Training
Optimizing carbohydrate timing ensures glycogen synthesis for intense exercise sessions.
✦ Hormonal Health & Dietary Consistency
Maintaining fat intake above 20-25% of total energy supports endocrine hormone production.
⚠ Common mistakes
- Cutting Fats Too Low: Reducing dietary fat below 15% of total calories can trigger hormonal imbalances and fatigue.
- Ignoring Meal Timing & Protein Distribution: Spacing protein across 3 to 5 meals optimizes muscle protein synthesis throughout the day.
FAQ (6)
Do I need to weigh my food raw or cooked?
Weighing food raw is significantly more accurate because cooking alters water content inconsistently.
What is the difference between macros and calories?
Calories measure total energy, while macros represent the specific nutrient components (proteins, carbs, fats) that provide that energy.
What happens to my weight, height or other health data?
It never leaves your phone. BMI, BMR, body-fat — all computed on-device, no upload, no account. That's intentional for health data: you can check a BMI of 22.8 or a TDEE of 2,100 kcal without worrying about a server log. Closing the tab clears the form from memory.
Does it work offline at the gym or on a plane?
Yep. Once the page has loaded, the calculators are fully offline-first. I've used the pace and BMI tools in airplane mode between flights — no spinner, no retry, just instant numbers. Same for sleep cycles if you're planning a shift.
Can my doctor rely on these numbers?
They're solid estimates using published formulas (WHO for BMI, Mifflin-St Jeor for BMR, CKD-EPI for GFR) but they're not a diagnosis. Think of them as a conversation starter: good for tracking trends, but your GP or nephrologist should interpret GFR, heart age or pregnancy dates with labs and context. We link the sources at the bottom for that reason.
How can I share my result with a trainer or doctor?
Use 'Share Link' in the results panel. It builds a URL with your inputs — for example BMI 70kg/175cm — so they see exactly what you entered. No data is stored on our side, the link just carries the numbers.
Sources & References
⚠ Health Disclaimer
This tool provides estimates for informational purposes only and does not constitute medical, veterinary, or professional advice. Always consult a qualified healthcare professional before making decisions about your health or treatment.