Macro Calculator

Enter the daily calories you are aiming for and pick one of four preset splits. The tool takes each macro's share of the calories and divides by its energy value, 4 kcal per gram for carbs and protein and 9 for fat:

grams = calories × percentage ÷ 100 ÷ 4 (or ÷ 9 for fat)

The default, 2,200 kcal on the balanced split (40% carbs, 30% protein, 30% fat), gives 220 g carbs, 165 g protein and 73 g fat. The tool doesn't work out your calorie target; the Calorie (TDEE) Calculator gives a starting estimate you can bring here.

Fat grams look small next to the others because each gram carries more than twice the energy. On the keto split at 2,200 kcal, the 65% fat share is 1,430 kcal, close to two-thirds of the day, yet it shows as only 159 g.

Each figure is rounded to a whole gram on its own. Multiply them back out and you land a few calories off the target: 220 × 4 + 165 × 4 + 73 × 9 = 2,197 kcal for the balanced split, and the low-carb split at 2,200 comes back as 2,206. The difference is rounding, not an error.

Here, protein is a percentage of calories, so it rises and falls with your calorie target rather than with your size. Dropping from 2,200 to 1,800 kcal on the balanced split cuts protein from 165 g to 135 g, even though your body hasn't changed.

It is worth comparing the result with a weight-based figure. The adult RDA for protein is 0.8 g per kg of body weight a day, which is 56 g for a 70 kg person. The Protein Intake Calculator on this site works from body weight and gives ranges by goal. If the two disagree a lot, it tells you the preset split may not suit your calorie level.

Like any of these tools, the output is an estimate, not a diagnosis or a prescribed diet.