Macro Calculator
Find your daily protein, carbs and fat
Free Macro Calculator — Protein, Carbs and Fat
Daily calories and macro grams tailored to your goal
This macro calculator finds your daily calorie needs (TDEE) with the Mifflin-St Jeor formula, adjusts them for your goal (lose, maintain, gain) and splits them into daily grams of protein, carbs and fat based on your diet style. Switch between balanced (30P/40C/30F), low-carb (40P/20C/40F) and athlete (30P/50C/20F) presets. Results use 4 kcal per gram of protein and carbs, 9 kcal per gram of fat. Everything runs in your browser and your data never leaves your device.
Features
All Three Macros
Daily protein, carbs and fat in grams
Goal-Based
Calories adjusted for losing, maintaining or gaining
Three Diet Styles
Balanced, low-carb and athlete presets
Private & Free
All calculations happen in your browser
Macro Splits & Calorie Values
How macros are set
- Protein: ~1.6–2.2 g/kg based on your weight and activity
- Fat: a share of your calorie target (by diet preference)
- Carbs: the calories left after protein and fat
- Balanced / Low-carb / High-carb shift the fat–carb balance
Calorie values
- 1 g protein = 4 kcal
- 1 g carbohydrate = 4 kcal
- 1 g fat = 9 kcal
- Loss goal: TDEE − 500 kcal, gain: +300 kcal
Frequently Asked Questions
How are my macros calculated?
First your BMR via Mifflin-St Jeor, then TDEE via your activity multiplier; calories are adjusted for your goal and split into grams by the ratio you pick.
Which style should I pick to lose weight?
The calorie deficit does the work; the split is preference. Higher protein (the low-carb preset) helps most people with satiety and muscle retention while dieting.
How much protein do I need?
0.8–1.2 g/kg is fine for general health; 1.6–2.2 g/kg is the common recommendation for people who train regularly.
Are the results exact?
Formulas are solid population-based estimates; real needs can vary ±10%. Track for 2-3 weeks and adjust calories to results. This tool is informational, not medical advice.
Is it free, and is my data stored?
Completely free — calculations run in your browser and nothing is sent to a server.