Macro Calculator: Protein, Carbs and Fat for Your Goal

Short answer

Macros are the grams of protein, carbohydrate and fat you eat each day. The calculator sets your calories from your TDEE and goal, sets protein from your body weight, gives 25% of the calories to fat and fills the rest with carbs.

Example with made-up numbers: an 80 kg person with a TDEE of 2,760 kcal who wants to lose fat gets 2,208 kcal a day, split into 144 g of protein, 61 g of fat and 270 g of carbs.

How the numbers are calculated

1. Calorie target = TDEE × 0.8 to lose, × 1 to maintain or × 1.1 to gain.
2. Protein (g) = body weight (kg) × your protein target. The default is 1.8 g/kg, and you can set anything from 1.2 to 2.6.
3. Fat = 25% of the calorie target, divided by 9 to get grams.
4. Carbs = whatever calories are left, divided by 4 to get grams.

The kcal per gram are the usual 4 for protein, 4 for carbs and 9 for fat. If you don't know your TDEE, fill in the same inputs as the TDEE calculator and it is worked out for you.

The example for all three goals

Same 80 kg person, TDEE 2,760 kcal, protein at 1.8 g/kg:

Protein stays the same across the three goals. Fat and carbs go up and down with calories.

Why these defaults

• Protein at 1.8 g/kg sits inside the 1.4 to 2.0 g/kg range the International Society of Sports Nutrition gives for most people who exercise (Jäger et al., 2017). In a meta-analysis of 49 trials, extra protein stopped adding fat-free mass at about 1.6 g/kg a day on average, with a confidence interval that reached 2.2 g/kg (Morton et al., 2018). During a diet, higher intakes may help keep muscle, which is why the slider goes up to 2.6.
• Fat at 25% of calories falls inside the 15 to 30% range suggested in a review of contest prep for natural bodybuilders (Helms, Aragon & Fitschen, 2014).
• The 20% cut is moderate. In the example it is 552 kcal a day, which by the usual 7,700 kcal per kg rule is about 0.5 kg a week, around 0.6% of body weight. That same review suggests losing 0.5 to 1% of body weight a week to hold on to muscle.

How to use your macros

Get calories and protein right first. How you split the rest between carbs and fat matters less from one day to the next, so a day with more carbs and less fat is fine as long as the totals are close.

Weigh your food for a week or two to learn what your portions look like, then check your weekly average body weight. If it doesn't move the way you want after two or three weeks, change calories by taking from or adding to carbs and fat, and leave protein where it is.

Limits

Every number here starts from an estimated TDEE, so the macros carry the same error. Protein per kg of total body weight gives a high number for someone with a lot of body fat; some people use their goal weight instead. If you have kidney disease, diabetes or another medical condition, are pregnant, or have a history of eating disorders, set your targets with a doctor or a registered dietitian.