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How much protein, carbs, and fat to eat each day

Daily protein, carbs, and fat in grams from your goal

These calculators provide estimates based on population-level formulas and do not replace assessment by a dietitian, physician or exercise professional.

Your data

Biological sex
Metabolic formulas use different constants by biological sex.
3–5 sessions per week
Goal
Balanced

Put the macro split on your plate in FITTA

FITTA applies protein, carbs, and fat to the day’s meals and updates the plan when the goal changes.

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Practical guide

How to use FITTA better.

Protein, carbohydrate, and fat are the three energy-bearing nutrients: 4 kcal per gram for protein and carbs, 9 kcal per gram for fat. This calculator estimates daily expenditure, shifts calories toward fat loss, maintenance, or muscle gain, and returns the three targets in grams instead of a free-floating percentage. It is a starting point for people who train and need a measurable plate. The output is a population-level estimate. A dietitian or physician should revise it when a medical condition is in play.

What macros are and why grams beat a fixed ratio

Macros are not a diet brand. They are the three nutrient classes that carry energy: protein and carbohydrate at 4 kcal per gram, fat at 9 kcal. Alcohol is about 7 kcal per gram and is left out. The math works when protein and fat clear a floor and carbohydrate fills the energy that remains.

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A locked 40/40/20 split forces protein into a percentage and ignores body weight. The stable path sets protein in grams per kilogram, sets fat as a share of calories, and lets carbs close the ledger. Protein repairs tissue and raises satiety. Fat carries fat-soluble vitamins and feeds hormones. Carbs restore glycogen and support training. None of them burns fat on its own.

  • Protein and carbs: 4 kcal/g (Atwater); fat: 9 kcal/g
  • Anchor in g/kg, not a fixed 40/40/20 split
  • Carbs are the residual after protein and fat

How this calculator builds the split

Four steps. BMR from Mifflin-St Jeor (1990): men, 10 × kg + 6.25 × cm − 5 × age + 5; women, the same sum with −161 instead of +5. TDEE = BMR × PAL: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 athlete.

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One kilogram of adipose tissue is about 7,700 kcal, the same 3,500 kcal per pound rule in US texts. A 0.5 kg (about 1.1 lb) weekly loss needs 0.5 × 7,700 / 7 = 550 kcal/day. A 0.25 kg weekly gain needs 275 kcal. Maintenance uses TDEE. The target never falls below 60% of TDEE.

Intermediate protein is 2.0 g/kg in a deficit (0.91 g/lb), 1.6 g/kg at maintenance (0.73 g/lb), and 1.8 g/kg in a surplus (0.82 g/lb). Fat (g) = (kcal × %) / 9, default 25%, with 20%, 30%, and 35%. Carbs (g) = (kcal − protein × 4 − fat × 9) / 4. If protein and fat blow the cap, carbs clamp at zero. Example: 30-year-old man, 75 kg (165 lb), 175 cm (5 ft 9 in), PAL 1.55, 0.5 kg/week loss, fat at 25%. BMR = 10 × 75 + 6.25 × 175 − 5 × 30 + 5 = 1,698.75 kcal. TDEE ≈ 2,633 kcal. Target = 2,083 kcal. Protein 150 g, fat ≈ 58 g, carbs ≈ 241 g.

  • Mifflin-St Jeor + PAL 1.2 / 1.375 / 1.55 / 1.725 / 1.9
  • 7,700 kcal/kg (≈ 3,500 kcal/lb); floor at 60% of TDEE
  • Protein 2.0 / 1.6 / 1.8 g/kg; fat = (kcal × %) / 9; carbs = remainder / 4

How to read protein, carbs, and fat

The headline number is the calorie target for the goal, not TDEE. In a deficit, protein rises to 2.0 g/kg and carbs shrink. In a surplus, the extra 275 kcal land mostly on carbs; protein stays at 1.8 g/kg. Extra muscle needs progressive training and energy, not double protein.

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Compare grams, not just the percentage. 150 g at 2,083 kcal is about 29% of energy; the same 150 g at 2,900 kcal is 21%. Use today’s weight, not the goal weight. Recalculate every 4 to 6 weeks or after a 3–4 kg (7–9 lb) change.

If carbs fall under about 2 g/kg (0.9 g/lb) with fat at 35%, training volume usually suffers. Drop fat to 20–25% before you cut protein. Fat under 15–20% of calories for a long stretch is unnecessary for most people and makes essential fatty acids harder to hit.

Common mistakes when setting macros

Marking very active and then subtracting workout calories inflates TDEE: the PAL factor already includes that band’s training. Copying 40/40/20 ignores weight and deficit size; a 55 kg woman in a small cut can land on too little protein. This page uses total body weight. Without a measured body-fat percent, 1.6 to 2.0 g/kg of total weight is the safer start.

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Macros do not replace fiber and vegetables. Do not rebuild the target after every 0.4 kg on the scale: glycogen and sodium shift 1 to 2 kg. Hold the split 14 to 21 days before moving calories more than 5 to 10%.

  • Do not double-count training after picking PAL
  • Do not force 40/40/20 without weight and deficit
  • Do not use lean mass unless body fat was measured
  • Do not reset the target after every scale wiggle

How to put the numbers on the plate and in training

Split protein across 3 to 5 meals of 25 to 40 g. Dense sources: chicken breast (about 31 g per 100 g grilled), a whole egg (about 6.3 g), Greek yogurt, whey, fish, lean meat, tofu, and legumes. Put most carbs in the meals around training: rice, potatoes, bread, oats, fruit. If performance and hunger drop, move 30 to 50 g from the rest day to the hard day and keep the weekly average. Keep a heavy fat load out of the meal right before training if it slows gastric emptying.

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FITTA applies the same goal to the meal plan and the food log. This page opens the math; the app puts the target on the menu and on progress. Estimate, not a clinical prescription: pregnancy, kidney disease, insulin-treated diabetes, and aggressive cuts belong with a dietitian.

Which dietary fat percentage to pick

Twenty percent frees more carbohydrate and fits high volume, HIIT, and endurance. Twenty-five percent is this calculator’s default. Thirty percent raises satiety. Thirty-five percent is moderate low carb, not ketosis: carbs remain unless the deficit is already deep. Nutritional ketosis usually needs fewer than 50 g of carbohydrate; this calculator only gets close when protein and fat already fill almost the whole budget.

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In a surplus, 20 to 25% fat leaves room for the carbs that support volume. In a long deficit, 25 to 30% helps palatability without giving up the protein floor.

Frequently asked questions

How do I calculate my macros for fat loss?

Estimate TDEE with Mifflin-St Jeor times the PAL factor. Subtract 550 kcal for a 0.5 kg (about 1.1 lb) weekly loss. Set protein at 2.0 g per kg, put 20 to 30% of calories in fat, and divide the rest by 4 for carbs in grams. Recalculate after a 3 to 4 kg change. It is an estimate, not a substitute for a dietitian.

How much protein per kg of body weight?

This calculator uses the intermediate band: 2.0 g per kg in a deficit (0.91 g/lb), 1.6 g per kg at maintenance (0.73 g/lb), and 1.8 g per kg in a surplus (0.82 g/lb). FITTA’s full matrix runs from 1.4 g/kg for a beginner at maintenance to 2.4 g/kg for an advanced lifter in a cut. In marked obesity, a professional may anchor to lean mass.

What is the best macro ratio for fat loss?

There is no universal ratio. With protein anchored in g/kg and fat at 25% of calories, a typical deficit lands near 30/45/25. At maintenance or in a surplus, carbs rise and protein as a percent falls even when grams stay put. Pick the fat percent from adherence and training volume, not from a social-media template.

Do I need to cut carbs to lose fat?

No. Body fat falls when calories stay below TDEE. Cutting carbs is only one way to open that gap. People who train with real volume usually keep about 2 to 3 g of carbs per kg to hold performance. If carbs get too low, drop fat from 35% to 20–25% before you touch protein.

Should macros be different on rest days?

The weekly average matters more than any single day. Holding protein and fat steady and shifting 30 to 50 g of carbs from a rest day to a hard day is enough for most people. It is not required. If the routine is simpler, use the same target every day and close the weekly mean.

How to calculate macros for muscle gain?

Add about 275 kcal to TDEE for a 0.25 kg per week pace. Protein at 1.8 g per kg, fat at 20 to 25% of calories, and the rest in carbs to support volume. A larger surplus speeds fat gain along with muscle. Recalculate every 4 to 6 weeks as body weight rises.

Are online macro calculators accurate?

They are population estimates with published formulas, not an individual measurement. Mifflin-St Jeor is off by about 10% on average for expenditure. Body weight, adherence, and training decide the real outcome. Run the numbers for 2 to 3 weeks, compare average weight and performance, then move calories 5 to 10%. Not a substitute for a dietitian.

Keep exploring

Daily calorie calculator

Daily target for fat loss, maintenance or muscle gain, plus time to goal weight

Protein calculator

Daily protein in g/kg from your goal and training level

TDEE Calculator

Estimate daily calorie burn with Mifflin-St Jeor and a 1.2–1.9 activity factor

These calculators provide estimates based on population-level formulas and do not replace assessment by a dietitian, physician or exercise professional.