Free Macro Calculator Online
Use this free macro calculator to find your daily protein, carb, and fat targets based on your body stats, activity level, and fitness goal. The macro calculator uses the Mifflin-St Jeor equation to estimate your calorie needs, then splits those calories into goal-specific macronutrient ratios you can start using today.
Daily Calorie Target
Enter your details above
How the Macro Calculator Works
This free online macro calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), then multiplies by your activity factor to get your Total Daily Energy Expenditure. For a 30-year-old male at 175 cm and 75 kg who exercises 3–5 days per week, that's roughly 2,450 calories per day at maintenance.
Next, the macro calculator applies a goal-specific ratio to split those calories into grams of protein, carbs, and fat. For fat loss, it subtracts 500 calories and uses a 40/30/30 split. For muscle building, it adds 300 calories with a 30/45/25 split. The result is a concrete daily gram target for each macronutrient.
Protein and carbs each contain 4 calories per gram, while fat contains 9 calories per gram. The free macro calculator handles all the math so you can focus on meal planning. Recalculate online every 4–5 kg of body weight change.
Macro Ratios by Goal
| Goal | Protein | Carbs | Fat |
|---|---|---|---|
| Lose Weight | 40% | 30% | 30% |
| Maintain Weight | 30% | 40% | 30% |
| Build Muscle | 30% | 45% | 25% |
Protein Intake Guidelines
| Population Group | Recommended Protein |
|---|---|
| Sedentary adult | 0.8 g/kg |
| Recreational exerciser | 1.0–1.4 g/kg |
| Endurance athlete | 1.2–1.6 g/kg |
| Strength / power athlete | 1.6–2.2 g/kg |
| Fat-loss diet (active) | 1.8–2.4 g/kg |
The macro calculator sets protein based on percentage of total calories, but you can cross-check with these per-kilogram guidelines to ensure you're in the right range for your training level.
Why Tracking Macros Beats Counting Calories Alone
Calories tell you how much to eat; macros tell you what to eat. Two diets at 2,000 calories can produce dramatically different results depending on the protein-to-carb-to-fat ratio. A high-protein macro split preserves muscle during a cut, while extra carbs fuel performance during a bulk. This free macro calculator gives you both numbers — calories and macros — in one step.
Research consistently shows that people who track macronutrients achieve better body composition results than those who track calories alone. The macro calculator makes this practical by converting percentages into actual grams you can measure and log.
Tips for Hitting Your Macro Targets
Prep protein sources in bulk — chicken breast, eggs, Greek yogurt, and tofu are macro-friendly staples.
Use a food scale for the first 2 weeks; eyeballing portions is the leading cause of macro tracking errors.
On training days, shift 5–10% of your fat calories toward carbs for better workout performance.
Recalculate your macros with this free calculator every 4–5 kg of body weight change to stay on track.
Frequently Asked Questions
Disclaimer: This free online macro calculator provides general estimates for informational purposes only. Individual macronutrient needs vary based on body composition, medical conditions, and training intensity. Consult a registered dietitian or healthcare provider before making significant dietary changes. This free tool does not replace professional nutritional guidance.
More Health Calculators
BMI Calculator
Calculate your Body Mass Index and interpret your weight category.
Calorie Calculator
Find out how many calories you need daily to reach your goals.
Calorie Deficit Calculator
Calculate your personalized calorie deficit target to lose weight safely.
BMR Calculator
Calculate your Basal Metabolic Rate to understand energy at rest.