Body & composition
Macro Calculator
Use this free macro calculator to find your daily calories and how many grams of protein, carbs and fat to aim for, based on your body, activity and goal.
- Free to use
- Works on your phone
- Nothing saved or shared
How to use this macro calculator for weight loss or any goal
This macro calculator works out your daily macros in three simple steps, whether you want fat loss, maintenance, or steady weight gain.
- Choose your sex and your preferred units.
- Enter your age, height and weight, then pick your activity level and goal.
- Press Calculate my macros to see your daily calories and gram targets.
What the numbers mean
The big number is roughly how many calories your body uses in a day at your chosen goal. Below it, your macros show how to make up those calories from the three energy nutrients:
- Protein repairs muscle and keeps you full.
- Carbohydrate is your body's main everyday fuel.
- Fat supports hormones and helps you absorb vitamins.
Macro calculator goals
Your goal changes only the calorie target. The split between protein, carbs and fat stays the same. As a macro calculator for fat loss it trims calories below maintenance, while keeping protein high to protect muscle, a target you can fine tune with our protein intake calculator.
| Goal | Calorie change | Best for |
|---|---|---|
| Lose weight | About 20% below maintenance | Fat loss while keeping protein high |
| Maintain weight | At maintenance | Staying where you are |
| Gain weight | About 15% above maintenance | Building muscle alongside training |
Using this sensibly
Treat these figures as a friendly starting point, not a strict diet. Whether you use this as a weight loss macro calculator or to support steady muscle gain, pairing it with a body fat percentage calculator to track changes in your body composition, aiming for enough protein and a reasonable calorie total, while eating plenty of vegetables and whole foods, matters far more than hitting every gram. If you have a health condition, check any big diet change with your doctor first.
Answers
Frequently asked questions
What are macros?
Macros, short for macronutrients, are the three nutrients that give you energy: protein, carbohydrate and fat. A macro calculator works out how many grams of each to aim for in a day, based on the calories your body needs.
How are my daily calories worked out?
First the tool estimates the energy your body uses at rest, using the Mifflin-St Jeor equation, then it adjusts for how active you are. Finally it nudges the total up or down a little depending on whether you want to lose, keep, or gain weight.
What is a good macro split?
This tool uses a balanced split of about 30% protein, 40% carbohydrate and 30% fat, which suits most people. There is no single perfect split, and your needs may differ, especially with a health condition or a specific training goal.
Should I weigh all my food?
You do not have to. Many people use these numbers as a loose guide rather than weighing every gram. Even roughly aiming for enough protein and not too many calories makes a real difference over time.
What macros should I eat for weight loss?
For weight loss, keeping protein high helps protect muscle and keeps you full. This tool uses a balanced split of about 30 percent protein, 40 percent carbohydrate and 30 percent fat on a calorie target around 20 percent below maintenance. You can adjust the split to suit how you feel and any advice from your doctor.
What macros should I eat to build muscle?
Pick the gain goal, which sets a small calorie surplus, and keep your protein high to support new muscle alongside your training. The tool works out the grams of protein, carbohydrate and fat for you, so you can see exactly what to aim for each day.
How many calories should my macros add up to?
Your protein, carbohydrate and fat grams together add up to the daily calorie target shown at the top of your result, so the macros and the calories always match. If you eat the grams the tool gives you, you are also hitting your calorie goal for the day.