MWC

Tools/Macro Calculator

Macro Calculator

Once you know your TDEE, the next step is dividing those calories across protein, carbohydrates, and fat. This calculator adjusts your calorie target based on your goal and outputs gram targets for each macronutrient. Protein and carbs contain 4 kcal per gram; fat contains 9 kcal per gram.

Not sure? Calculate your TDEE first

Understanding the splits

Cutting (40/30/30): Higher protein preserves muscle in a deficit. Lower carbs reduce total calories while fat supports hormone function.

Maintenance (30/40/30): A balanced split appropriate for body recomposition or maintaining weight.

Bulking (25/50/25): Higher carbohydrates fuel intense training sessions and support muscle protein synthesis via insulin response.

These splits are starting points. Adjust based on how you feel during training and how your body responds over 2–4 weeks.

Related

TDEE CalculatorBody Fat CalculatorTraining ProgramsNutrition Blog

How the Calculation Works

The calculator starts from your calorie target — TDEE adjusted for your goal (a deficit for cutting, a modest surplus for bulking) — and allocates it across the three macronutrients in priority order. Protein is set first in grams per kilogram of body weight, because it is the macro with the strongest evidence behind a specific target. Fat is set second as a floor for hormonal health. Carbohydrates get everything left over.

Protein: 1.6–2.2 g × bodyweight(kg) → 4 kcal/g
Fat: 0.6–1.0 g × bodyweight(kg) → 9 kcal/g
Carbs: (target kcal − protein kcal − fat kcal) ÷ 4

This grams-per-kilogram approach beats fixed percentage splits (like 40/30/30) because your protein requirement is tied to your body mass and training, not to how many calories you happen to be eating. On a cut, percentages would slash protein exactly when you need it most.

A Worked Example

An 80 kg lifter cutting on 2,400 kcal: protein at 2.0 g/kg = 160 g (640 kcal). Fat at 0.8 g/kg = 64 g (576 kcal). That leaves 2,400 − 640 − 576 = 1,184 kcal for carbs, or 296 g. Final targets: 160 g protein / 296 g carbs / 64 g fat. If the same lifter switched to a 3,000 kcal lean bulk, protein and fat barely move — nearly all of the extra 600 kcal goes to carbs, fueling harder training sessions.

Using Your Macros in Practice

Hit protein consistently, treat carbs and fat as flexible. A daily margin of ±5-10 g per macro is well within the noise — food labels themselves carry that much error. Spread protein across 3-5 meals of 25-50 g each for convenience (total daily intake is what matters most), and put a meaningful portion of your carbs around training if you like the performance boost.

Reassess every few weeks against real-world results: if your weight trend is off target, the adjustment goes into calories — mostly via carbs — while protein stays anchored to body weight. When your weight changes by more than 3-4 kg, rerun both the TDEE calculator and this one, since every target scales with body mass.

Frequently Asked Questions

How much protein do I actually need?+

For people who lift, the evidence supports 1.6-2.2 g per kg of body weight per day. Go toward the top of that range when cutting — higher protein preserves muscle in a deficit — and the middle is plenty when bulking or maintaining.

Why does the calculator set fat as a minimum?+

Dietary fat supports hormone production and vitamin absorption, so it should not drop below roughly 0.6-0.8 g per kg of body weight for long. Once protein and minimum fat are covered, the remaining calories go to carbs, which fuel training.

Do macro ratios like 40/30/30 work?+

Fixed percentage splits are a blunt instrument — they scale protein with calories rather than body weight, so they under-shoot protein on a cut and over-shoot it on a big bulk. Setting protein and fat in grams per kg first, then filling with carbs, is more precise.

Do I need to hit my macros exactly every day?+

No. Within ±5-10 g per macro is more than accurate enough, and weekly averages matter more than any single day. Protein is the one worth being most consistent with; carbs and fat can flex against each other at equal calories.

Should I change my macros on rest days?+

Optional. Some people shift 30-50 g of carbs from rest days to training days while keeping weekly calories identical. It may improve gym performance slightly, but total weekly intake and protein consistency drive almost all of the result.

Keep Going

Macro Guide

The complete guide to setting and adjusting your macros.

TDEE Calculator

Start here — macros are built from your maintenance calories.

Protein Intake Guide

How much protein per day the research actually supports.

AI Workout Generator

Match your nutrition targets with a training plan built for your goal.