How to Calculate Your Macros for Weight Loss
Counting calories is the blunt instrument of weight loss. Counting macros is the precision tool. Here's how to find your exact protein, carbohydrate, and fat targets — and why the ratio matters as much as the total.
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What are macros?
"Macros" is short for macronutrients — the three categories of nutrients that provide calories: protein, carbohydrates, and fat. Every food you eat is made up of some combination of these three, and each one plays a different role in your body.
- Protein (4 cal/g)Builds and preserves muscle mass. Critical during weight loss to prevent losing muscle along with fat.
- Carbohydrates (4 cal/g)Your body's preferred energy source. Fuels workouts, brain function, and daily activity.
- Fat (9 cal/g)Supports hormone production, vitamin absorption, and satiety. Despite the name, dietary fat does not directly cause body fat gain.
When you track macros instead of just calories, you ensure that the weight you lose comes from fat — not muscle. That distinction matters enormously for how you look, feel, and perform.
Step 1: Calculate your TDEE
Before you can set macro targets, you need to know how many calories your body burns in a day. This is called your Total Daily Energy Expenditure (TDEE).
TDEE is calculated in two stages. First, you find your Basal Metabolic Rate (BMR) — the calories your body needs at complete rest just to maintain basic functions like breathing, circulation, and cell repair. Then you multiply by an activity factor to account for how much you move.
The most accurate formula for BMR is the Mifflin-St Jeor equation:
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
Multiply your BMR by your activity level to get TDEE:
| Activity Level | Description | Multiplier |
|---|---|---|
| Sedentary | Desk job, little to no exercise | × 1.2 |
| Lightly active | Light exercise 1–3 days/week | × 1.375 |
| Moderately active | Moderate exercise 3–5 days/week | × 1.55 |
| Very active | Hard exercise 6–7 days/week | × 1.725 |
| Extremely active | Physical job + daily training | × 1.9 |
Use our TDEE calculator to get your number instantly without doing the math manually.
Step 2: Set your calorie deficit
To lose weight, you need to eat fewer calories than you burn. The size of that deficit determines how fast you lose weight — and how much muscle you risk losing in the process.
| Deficit | Weekly Loss | Best For |
|---|---|---|
| 250 cal/day | ~0.25 kg / 0.5 lb | Minimal muscle loss, slow and steady |
| 500 cal/day | ~0.5 kg / 1 lb | Standard recommendation, good balance |
| 750 cal/day | ~0.75 kg / 1.5 lb | Faster loss, requires higher protein |
| 1,000 cal/day | ~1 kg / 2 lb | Maximum advised; monitor energy closely |
A 500-calorie deficit is the most commonly recommended starting point. If your TDEE is 2,400 calories, your daily calorie target for weight loss would be 1,900 calories.
Use our calorie deficit calculator to find the right deficit for your goals and timeline.
Step 3: Set your protein target first
Protein is the most important macro to get right during weight loss. It preserves lean muscle while you're in a deficit, keeps you fuller for longer, and has the highest thermic effect of any macronutrient — meaning your body burns more calories just digesting it.
The research consistently points to the same range:
Recommended protein intake for weight loss:
1.6–2.2g per kg of bodyweight (0.7–1.0g per lb)
Example: A 75kg (165 lb) person should target 120–165g of protein per day.
If you're heavier or have more fat to lose, base your protein target on your goal weight rather than your current weight. This prevents inflating your protein needs based on excess fat mass.
Our protein calculator gives you a personalized target based on your stats and activity level.
Step 4: Set your fat minimum
Fat should never go below a minimum threshold. It's essential for hormone regulation (including testosterone and estrogen), fat-soluble vitamin absorption (A, D, E, K), and general wellbeing. Going too low on fat can cause hormonal disruption, poor recovery, and persistent hunger.
Minimum fat intake:
0.8–1.0g per kg of bodyweight (0.35–0.45g per lb)
Example: A 75kg person should eat at least 60–75g of fat per day.
Beyond this minimum, fat intake is flexible. Any remaining calories after protein and a fat minimum can be split between fat and carbs based on your preference.
Step 5: Fill the rest with carbohydrates
Once you've set protein and fat, carbohydrates fill the remaining calories. They're not the enemy — they fuel your workouts, support thyroid function, and make dieting sustainable long-term.
Example calculation (75kg person, TDEE 2,400, 500 cal deficit):
Daily calorie target: 1,900 cal
Protein: 150g × 4 cal = 600 cal
Fat: 70g × 9 cal = 630 cal
Remaining for carbs: 1,900 − 600 − 630 = 670 cal
Carbs: 670 ÷ 4 = 167g
Final split: 150g protein / 167g carbs / 70g fat
Common macro splits for weight loss
If you'd rather start with a preset ratio and adjust from there, here are three approaches commonly used for fat loss:
| Approach | Protein | Carbs | Fat |
|---|---|---|---|
| Standard (balanced) | 30% | 40% | 30% |
| High protein | 40% | 30% | 30% |
| Low carb | 35% | 25% | 40% |
| Keto | 25% | 5% | 70% |
The best split is the one you can stick to. Research shows that high-protein diets consistently outperform other approaches for body composition, regardless of carb-to-fat ratio. Get protein right, keep a moderate deficit, and the specific carb/fat split matters less than you think.
When to adjust your macros
Your TDEE changes as you lose weight — a smaller body burns fewer calories. If fat loss stalls for 2–3 weeks despite hitting your targets consistently, it's time to recalculate. Don't just drop calories blindly; recalculate your TDEE based on your new weight first.
Other signs you need to adjust:
- Persistent fatigue or poor workout performance → increase carbs slightly
- Constant hunger → increase protein or fat, reduce deficit slightly
- Losing weight too fast (>1% bodyweight/week) → increase calories to protect muscle
- No progress after 3+ weeks → reduce calories by 100–150 or increase activity
Ready to find your numbers?
Use our free macro calculator to get your personalized protein, carb, and fat targets based on your weight, height, activity level, and goal.
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