Calculate your macros
Enter your details below. The calculator uses the Mifflin-St Jeor equation, so you only need age, weight, height, activity and goal — no account, no signup.
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How it works
1. Your BMR (calories burned at rest) is estimated with the Mifflin-St Jeor equation. 2. Activity multiplies BMR to give TDEE (total daily energy). 3. Your goal adjusts calories, then calories are split into protein (30%), carbohydrates (40%) and fat (30%).
Worked example: A 30-year-old man, 75 kg, 175 cm, moderately active, maintaining weight: BMR about 1,699 kcal, TDEE about 2,633 kcal — about 197 g protein, 263 g carbs and 88 g fat per day.
Macro split at a glance
| Macro | Share of calories | Calories per gram |
|---|---|---|
| Protein | 30% | 4 kcal |
| Carbohydrates | 40% | 4 kcal |
| Fat | 30% | 9 kcal |
Related calculators
Protein Calculator — how much protein do you need per day, from body weight and activity.
TDEE Calculator — your total daily energy expenditure, BMR and goal calories.
What are macros?
Protein builds and repairs muscle. Carbohydrates are the body's main quick energy source. Fat supports hormones and absorbs vitamins. Counting all three, not just calories, is why macro tracking works for many people.
Macro calculator for weight loss and muscle gain
For weight loss, this calculator subtracts 500 kcal from your TDEE, a steady deficit for most adults. For muscle gain, it adds 300 kcal, so you eat a little above maintenance while training. In both cases the protein, carb and fat grams change with the calorie total, because they are calculated from your adjusted calories, not fixed numbers.
Frequently Asked Questions
What is a macro calculator? A tool that estimates daily calories and protein, carb and fat grams from your body, activity and goal.
How many grams of protein do I need per day? It depends on body weight and goal. This calculator uses a standard protein target and shows the grams for your inputs; athletes and people building muscle usually need more than sedentary people.
What macro split does this calculator use? Protein 30%, carbohydrates 40% and fat 30% of daily calories. Protein and carbohydrates give 4 calories per gram, fat gives 9 calories per gram.
How is this different from a calorie calculator? A calorie calculator only gives total calories. A macro calculator also splits those calories into protein, carbs and fat, so you can plan meals, not just a calorie total.
Should I eat the same macros every day? Daily totals matter most. Small day-to-day variation is normal; consistency over weeks matters more than one perfect day.
Is this medical advice? No. This is general information only. Talk to a doctor or registered dietitian before changing your diet, especially if you are pregnant, have diabetes, kidney disease, or any health condition.