Macro Calculator
Calculate your daily protein, carbs, and fat targets based on your goal — cutting, maintenance, or bulking — using TDEE and popular macro splits.
What is Macro Calculator?
The macro calculator turns your calorie target into grams of protein, carbohydrates, and fat — the three macronutrients that make up everything you eat. Calories drive weight change; macros drive body composition, satiety, and gym performance.
Pick your goal (fat loss, maintenance, or muscle gain) and a macro split (balanced, high-protein, low-carb, or keto) and the calculator sets daily targets you can track in MyFitnessPal, Cronometer, or similar apps.
Formula
Step 1 — BMR (Mifflin-St Jeor):
- Men: 10×kg + 6.25×cm − 5×age + 5
- Women: 10×kg + 6.25×cm − 5×age − 161
Step 2 — TDEE = BMR × activity multiplier (1.2 sedentary → 1.9 athlete).
Step 3 — Calorie target = TDEE × goal multiplier: cut 0.8, mild cut 0.9, maintain 1.0, lean bulk 1.1, bulk 1.2. Floor is 1,200 cal/day.
Step 4 — Macro grams: protein & carbs = 4 cal/g, fat = 9 cal/g. Multiply calories × macro percent ÷ energy density.
Worked example
A 30-year-old man, 5'9" (69 in), 170 lb, moderately active, lean bulk on a high-protein plan:
- BMR ≈ 1,722 cal → TDEE ≈ 2,669 cal
- Calorie target = 2,669 × 1.1 ≈ 2,936 cal/day
- Protein = 2,936 × 0.40 / 4 = 294 g
- Carbs = 2,936 × 0.40 / 4 = 294 g
- Fat = 2,936 × 0.20 / 9 = 65 g
That is ~1.7 g of protein per pound of body weight — near the upper end of the research-backed range for muscle building.
How to use this calculator
- Enter sex, age, height, and weight in your preferred units.
- Pick the activity level that matches your average week. Most lifters with a desk job land on moderately active.
- Choose a goal. For fat loss, start with mild cut (−10%); go deeper only if progress stalls.
- Pick a macro plan. High-protein is the safest default for most people trying to recomp or lose fat while preserving muscle.
- Track total intake for 2 weeks — if the scale isn't moving as expected, adjust calories by ±100–200.
Frequently asked questions
How much protein do I actually need?
For general health, the RDA is 0.36 g/lb body weight (~55 g for a 150-lb adult). For muscle building or fat loss while preserving muscle, research (Morton et al., 2018) supports 0.7–1.0 g/lb of body weight, with diminishing returns above 1.0 g/lb. Athletes in a steep deficit may benefit from up to 1.2 g/lb.
Do I need to hit macros exactly every day?
No. Aim to be within ±10 g of each macro target. Protein is the most important to hit consistently; carbs and fat can swap day-to-day as long as total calories stay in range. Think of macros as a weekly average, not a daily mandate.
What's the difference between balanced and Zone diet splits?
They're functionally identical at 30% protein / 40% carbs / 30% fat. The Zone diet by Dr. Barry Sears popularized this ratio in the 1990s; "balanced" is the generic industry term for the same macro profile.
Is keto worth trying?
Keto (5% carbs) can help with appetite control and initial water-weight loss, and is medically used for drug-resistant epilepsy. For weight loss alone, meta-analyses show it performs about the same as other calorie-matched diets — pick what you can stick to. Keto is harder to fuel for high-intensity training.
How often should I recalculate?
Every 10–15 lb change in body weight, or every 4–6 weeks during an active cut or bulk. Your metabolism adapts as you lose weight — the same calories that produced a deficit at 200 lb may be maintenance at 180 lb.