Macro Calculator
Calculate your daily protein, carbs, and fat needs. Presets for balanced, low-carb, high-protein, and keto diets based on your goals.
Macros are protein, carbs, and fat: the building blocks of your diet. A balanced split is 30% protein, 40% carbs, 30% fat.
Calculate your exact daily macro needs below.
Your Details
Little or no exercise
Light exercise 1-3 days/week
Moderate exercise 3-5 days/week
Hard exercise 6-7 days/week
Very hard exercise & physical job
~2 lbs/week
~1 lb/week
~0.5 lb/week
Stay same weight
~0.5 lb/week
~1 lb/week
~2 lbs/week
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Last updated: January 2026 • Built with care by iForge Apps
What Are Macronutrients?
Macronutrients — protein, carbohydrates, and fat — are the three nutrients your body needs in large quantities every day. Unlike micronutrients (vitamins and minerals), macros provide the calories that fuel everything from breathing to sprinting. Each macro serves a distinct role:
- Protein (4 calories per gram) — builds and repairs muscle tissue, produces enzymes and hormones, and has the highest satiety of any macro. Your body breaks protein into amino acids, nine of which are "essential" (you must get them from food).
- Carbohydrates (4 calories per gram) — your body's preferred energy source. Carbs fuel your brain (which uses ~120g of glucose daily), power muscle contractions during exercise, and replenish glycogen stores after training.
- Fat (9 calories per gram) — supports hormone production (testosterone, oestrogen), enables absorption of fat-soluble vitamins (A, D, E, K), protects organs, and provides long-lasting energy. Fat is the most calorie-dense macro at more than double the calories per gram of protein or carbs.
The saying "a calorie is a calorie" is misleading. Two thousand calories of chicken breast, sweet potatoes, and olive oil will have very different effects on your body composition, energy levels, and hunger compared to 2,000 calories of sweets and fizzy drinks. The source and ratio of your macros matter — which is exactly why tracking them gives better results than counting calories alone.
The Mifflin-St Jeor Equation
This calculator uses the Mifflin-St Jeor equation, published in 2005 and widely considered the most accurate predictive formula for estimating resting metabolic rate. It outperforms the older Harris-Benedict equation (1919) across all BMI ranges and is the formula recommended by the Academy of Nutrition and Dietetics.
How the calculation works:
- BMR (Basal Metabolic Rate) — calories your body burns at complete rest
- TDEE (Total Daily Energy Expenditure) — BMR × activity multiplier
- Target Calories — TDEE ± goal adjustment (deficit or surplus)
- Macro Split — target calories divided by your chosen ratio into protein, carbs, and fat grams
The formulas:
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Diet Presets Explained
Our calculator offers four evidence-based macro splits. Each suits different goals, activity levels, and metabolic profiles:
Balanced (30% Protein / 40% Carbs / 30% Fat)
The default recommendation from most registered dietitians. This split provides enough protein for muscle maintenance, sufficient carbohydrates to fuel moderate activity and brain function, and adequate fat for hormonal health. It's the best starting point if you're unsure which preset to choose, and works well for general fitness, moderate exercise (3-5 days per week), and overall health.
Low-Carb (40% Protein / 20% Carbs / 40% Fat)
Reduces carbohydrates while increasing protein and fat to compensate. This split benefits people who are insulin resistant, have PCOS, or are relatively sedentary. By limiting carbs to ~20% of calories, blood sugar stays more stable throughout the day. This is not the same as keto — you'll still consume 100-150g of carbs daily on a 2,000-calorie diet, enough to fuel moderate exercise without entering ketosis.
High-Protein (40% Protein / 35% Carbs / 25% Fat)
The go-to split for muscle building and aggressive fat loss. Protein has the highest thermic effect of any macro — your body burns 20-30% of protein calories just digesting it, compared to 5-10% for carbs and 0-3% for fat. This means 200 calories of protein effectively becomes ~150 usable calories. Bodybuilders, strength athletes, and anyone in a calorie deficit benefits from this split because high protein preserves lean mass while dieting.
Keto (25% Protein / 5% Carbs / 70% Fat)
The ketogenic diet restricts carbohydrates to roughly 20-50g per day (5% of calories), forcing your body to switch from glucose to ketones as its primary fuel source — a metabolic state called ketosis. Expect a 2-4 week adaptation period often called "keto flu" (fatigue, headaches, brain fog) as your body adjusts. Keto can be effective for rapid fat loss and appetite suppression, but it's restrictive and difficult to sustain long-term. It's not ideal for high-intensity athletes who rely on glycogen for explosive movements.
Protein: The Most Important Macro
If you're going to track just one macro, make it protein. It builds muscle, preserves lean mass during a calorie deficit, keeps you full longer than carbs or fat, and has the highest thermic effect. Here's how much you need based on your goal:
| Goal | Protein (per kg bodyweight) | Example (80kg person) |
|---|---|---|
| General health | 0.8g/kg | 64g/day |
| Fat loss | 1.6–2.2g/kg | 128–176g/day |
| Muscle gain | 1.6–2.4g/kg | 128–192g/day |
| Athletes | 2.0–2.5g/kg | 160–200g/day |
Best sources: chicken breast (31g per 100g), eggs (6g each), Greek yoghurt (10g per 100g), whey protein (25g per scoop), lentils (9g per 100g cooked), tofu (8g per 100g). Aim for a mix of animal and plant sources for a complete amino acid profile. The protein timing myth — that you must eat within 30 minutes of training — has been largely debunked. Total daily intake matters far more than when you eat it.
Carbohydrates: Not the Enemy
Despite what diet culture suggests, carbohydrates are not inherently fattening. They're your body's preferred fuel for high-intensity exercise, brain function, and mood regulation. The key is choosing the right carbs in the right amounts.
- Simple carbs (sugar, white bread, sweets) are digested quickly, spike blood sugar, and leave you hungry again soon. Limit these.
- Complex carbs (oats, sweet potatoes, brown rice, whole grains) digest slowly, provide sustained energy, and are packed with fibre and micronutrients. Prioritise these.
- Fibre is a special type of carbohydrate your body can't digest. It feeds gut bacteria, aids digestion, and increases satiety. Aim for 25-35g per day.
When to eat more carbs: on training days, before and after workouts, and during periods of high physical activity. When to eat fewer: on rest days, if you're sedentary, or if you have insulin resistance. The glycaemic index (GI) measures how quickly a food raises blood sugar — low-GI foods (lentils, most vegetables) are generally better choices than high-GI foods (white rice, watermelon) for sustained energy.
Fat: Essential, Not Optional
Dietary fat is not the villain it was made out to be in the 1990s. It's essential for hormone production (your body needs cholesterol to make testosterone and oestrogen), brain function (60% of your brain is fat), and absorbing fat-soluble vitamins A, D, E, and K. Cutting fat too low — below 20% of total calories — risks hormonal disruption, poor recovery, and nutrient deficiencies.
- Unsaturated fats (olive oil, avocado, nuts, fatty fish) — heart-healthy, anti-inflammatory. Make these the majority of your fat intake.
- Saturated fats (butter, cheese, red meat, coconut oil) — not as harmful as once believed, but keep to ~10% of total calories.
- Trans fats (hydrogenated oils, many processed foods) — genuinely harmful. Avoid entirely.
Best sources: extra virgin olive oil (14g fat per tablespoon), avocado (15g per half), almonds (14g per 28g), salmon (13g per 100g), eggs (5g each). Omega-3 fatty acids from fatty fish (salmon, mackerel, sardines) are particularly important — aim for 2-3 servings per week.
How to Track Macros
Tracking macros doesn't have to mean weighing every gram of food for the rest of your life. Here's a practical approach from simplest to most precise:
| Method | Accuracy | Best For |
|---|---|---|
| Hand-size portions | ±30% | Beginners, eating out, low-stress tracking |
| Measuring cups/spoons | ±15% | Home cooking, moderate accuracy needed |
| Digital food scale | ±5% | Precise tracking, competition prep, plateaus |
Hand-size guide: a palm of protein (~30g), a fist of carbs (~40g), a thumb of fat (~15g). This won't be perfect, but it's far better than guessing blindly.
The 80/20 rule: track strictly for 2-4 weeks to learn what portions actually look like. After that, most people can estimate with reasonable accuracy. Meal prepping 3-4 days of food at once makes tracking dramatically easier — you log once and eat the same meals multiple times.
Macro Splits for Specific Goals
Different goals require different macro ratios and calorie adjustments. Here's an evidence-based starting point for each:
| Goal | Protein | Carbs | Fat | Calorie Adjustment |
|---|---|---|---|---|
| Fat loss | 40% | 30% | 30% | −500 cal/day |
| Lean bulk | 30% | 45% | 25% | +250–500 cal/day |
| Body recomposition | 35% | 35% | 30% | Maintenance |
| Endurance athletes | 25% | 55% | 20% | Maintenance to +300 |
| Keto / low-carb | 25% | 5–20% | 55–70% | Varies by goal |
These are starting points — not rigid rules. Track your progress for 2-3 weeks, then adjust. If you're losing weight too fast (more than 1% of bodyweight per week), increase calories by 200. If you're not losing at all, decrease by 200. Small, consistent adjustments beat dramatic overhauls.
Common Macro Tracking Mistakes
❌ Not counting cooking oils and sauces
✅ A tablespoon of olive oil adds 120 calories and 14g of fat. Sauces can add 200-500 hidden calories per day. Measure or switch to cooking spray.
❌ Eyeballing portions
✅ Studies show most people underestimate portions by 30-50%. Use a food scale for at least 2 weeks to calibrate your eye.
❌ Ignoring liquid calories
✅ A large latte has 200+ calories. A smoothie can top 500. Alcohol is 7 cal/g with zero nutritional value. Log every drink.
❌ Only tracking on 'good' days
✅ Selective tracking gives a false picture. Your weekly average matters more than any single day. Track everything — including weekends.
❌ Obsessing over daily numbers
✅ A single day over your fat macro won't derail progress. Look at weekly averages. If you're within 10% of targets most days, you're doing well.
❌ Forgetting 'BLT' calories
✅ Bites, licks, and tastes while cooking add up. A handful of nuts here, a spoonful of peanut butter there — these can total 300+ untracked calories.
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How to use this tool
Enter your age, gender, height, weight, and activity level
Choose your weight goal and a diet preset
Click Calculate Macros to see your daily protein, carbs, and fat targets
Common uses
- Planning daily meals around specific protein, carb, and fat targets
- Following a keto, low-carb, or high-protein diet with precise gram counts
- Adjusting macros for cutting, bulking, or body recomposition goals
- Comparing different diet approaches side by side before committing
- Tracking macro splits alongside calorie targets for fitness programmes
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