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Macro Calculator

Split your daily calories into protein, carbs and fat

Age

Sex

Height

Weight

Activity

Goal

BMR formula

Body fat

Daily Calories

kcal

Enter calories (800-10000)

Diet Plan

Protein

Carbs

Fat

Macro Calculator — Complete Guide

Macronutrients — protein, carbohydrate and fat — are the three nutrients that supply energy. Your calorie total sets whether you gain or lose weight; the split between them shapes body composition, energy and hunger.

What this calculator does

Give it a daily calorie target and pick a diet plan. It converts the percentages behind that plan into grams of protein, carbohydrate and fat, then shows how many calories each contributes.

The formula

protein g = calories × protein% ÷ 4
carbs g = calories × carbs% ÷ 4
fat g = calories × fat% ÷ 9

Protein and carbohydrate deliver 4 calories per gram; fat delivers 9. Fat is more than twice as energy-dense, which is why fat grams are always the smallest number on the label.

Plan splits used here

Plan	Protein	Carbs	Fat
Balanced	30%	40%	30%
Low carb	35%	25%	40%
High protein	40%	35%	25%
Keto	25%	5%	70%

Choosing a split

Protein first. Most people do best between 1.6 and 2.2 g per kilogram of body weight when training, regardless of the plan name.
Fat has a floor. Very low fat diets can affect hormones; most guidelines suggest at least 0.5 g per kilogram.
Carbs are the flexible one. Fill the remainder with carbohydrate and adjust up or down by how you train and feel.
Adherence beats theory. The best split is the one you can hold for months, not weeks.

Use grams per kilogram as a cross-check: if the calculator gives you 120 g of protein at 80 kg, that is 1.5 g/kg — reasonable for maintenance but low for a serious lifter.

宏量营养素计算器完整使用指南

宏量营养素 —— 蛋白质、碳水化合物和脂肪 —— 是提供能量的三大营养素。热量总量决定你增重还是减重；三者之间的配比则影响身体成分、精力和饥饿感。

这个计算器能做什么

输入每日热量目标并选择一种饮食方案，它会把方案背后的百分比换算成蛋白质、碳水和脂肪的克数，并展示各自贡献的热量。

计算公式

蛋白质克数 = 热量 × 蛋白质% ÷ 4
碳水克数 = 热量 × 碳水% ÷ 4
脂肪克数 = 热量 × 脂肪% ÷ 9

蛋白质和碳水每克提供 4 千卡，脂肪每克 9 千卡。脂肪的能量密度是前两者的两倍多，这就是营养成分表上脂肪克数总是最小的原因。

本工具使用的方案配比

方案	蛋白质	碳水	脂肪
均衡	30%	40%	30%
低碳水	35%	25%	40%
高蛋白	40%	35%	25%
生酮	25%	5%	70%

怎么选配比

先定蛋白质。 对大多数训练者而言，每公斤体重 1.6-2.2 克是合适区间，与方案叫什么名字无关。
脂肪有下限。 极低脂饮食可能影响激素，多数指南建议至少每公斤体重 0.5 克。
碳水最灵活。 剩下的热量交给碳水，再按训练量和身体感受上下调整。
能坚持才有效。 最好的配比是你能坚持几个月、而不是几周的那个。

可以用「每公斤体重克数」交叉验证：若 80 公斤的人算出 120 克蛋白质，即 1.5 g/kg —— 维持尚可，但对认真训练者偏低。

Frequently Asked Questions

How do I calculate macros from calories?

Multiply your daily calories by each macronutrient's percentage, then divide by its calories per gram: protein and carbs are 4 kcal per gram, fat is 9. On 2,000 calories with 30% protein, that is 600 ÷ 4 = 150 g of protein.

What is a good macro split for weight loss?

A common starting point is 30% protein, 40% carbohydrate and 30% fat. Higher protein helps preserve muscle in a deficit and tends to keep you fuller, which is why many plans push protein to 35-40%.

Do macros matter more than calories?

For weight change, calories dominate. Macros affect body composition, satiety, training performance and how easy the diet is to stick to — which in practice decides whether the calorie target holds.

Last reviewed: October 5, 2026 · How we calculate · Sources: NIH, Academy of Nutrition and Dietetics