Macro Calculator: Protein, Carbs & Fat in Grams

How macros are calculated

Protein and carbohydrates each provide 4 calories per gram. Fat provides 9. Alcohol, if you drink, adds 7. To turn a calorie target and a percentage split into grams: grams = calories × percent ÷ calories per gram.

Worked example: 2,200 kcal with a 30/40/30 split. Protein: 2,200 × 0.30 ÷ 4 = 165 g. Carbs: 2,200 × 0.40 ÷ 4 = 220 g. Fat: 2,200 × 0.30 ÷ 9 = 73 g. Check: 165 × 4 + 220 × 4 + 73 × 9 = 660 + 880 + 657 = 2,197, within rounding of 2,200.

Set protein by body weight, not percentage

Percentages are convenient but can mislead. 30 percent protein is 165 g on 2,200 kcal, but only 120 g on 1,600 kcal. Research on people who lift weights supports roughly 1.6 to 2.2 g per kg of body weight, or 0.7 to 1 g per pound, especially during a calorie deficit.

A better method: set protein in grams first, set fat at 25 to 35 percent of calories, and give carbs whatever is left. For a 180-pound person at 2,200 kcal: 160 g protein (640 kcal), 30 percent fat (660 kcal, 73 g), leaving 900 kcal for 225 g of carbs. Convert back to percentages (29/41/30) and enter them here.

Common splits and who they suit

Balanced 30/40/30: a solid default for general fitness. Higher carb, around 25/50/25: endurance athletes and people training hard most days. Lower carb, around 35/25/40: people who feel better with fewer carbs or have been advised to reduce them. Keto sits around 20/5/75, with carbs under roughly 50 g a day.

The US Dietary Guidelines ranges for adults are 10 to 35 percent protein, 45 to 65 percent carbohydrate, and 20 to 35 percent fat. Most fitness splits sit at the high end for protein and the low end for carbs. For fat loss, total calories and protein matter more than the exact carb-to-fat ratio.

Percentages must total 100

The calculator shows the running total so you can catch mistakes. If your numbers add up to 105 percent, your gram targets will overshoot your calories by about 5 percent. Adjust one macro, usually carbs, until the total reads 100.

Adjusting macros for your goal

For fat loss, keep protein high, around 1 gram per pound of goal weight, and take the calorie cut mainly from carbs and fat. Higher protein reduces muscle loss and hunger. For muscle gain, a small surplus of 200 to 300 kcal a day is enough; more tends to add fat faster than muscle. Protein can come down slightly, to about 0.8 grams per pound, and carbs go up to fuel training.

For endurance training, carbs matter most. Athletes training more than an hour a day often need 5 to 7 grams of carbohydrate per kilogram of body weight, which for a 70 kg runner is 350 to 490 grams, well above what a 40 percent split provides.

Fiber, micronutrients, and food quality

Macros are not the whole picture. Aim for about 14 grams of fiber per 1,000 calories, which is 31 grams on a 2,200 kcal diet, as the Dietary Guidelines suggest. Most Americans get about half that. Fiber comes from the carb budget, so vegetables, beans, whole grains, and fruit are the efficient way to spend it.

Two diets with identical macros can differ enormously in vitamins, minerals, and satiety. Use your targets as a frame and fill them mostly with minimally processed foods.

Hitting your numbers in practice

Build meals around a protein source first: 4 oz of chicken breast has about 35 g protein; a cup of Greek yogurt about 20 g; two eggs about 12 g. Hitting within 10 g of protein and 5 percent of calories is plenty accurate. Track for two to four weeks to learn portions, then eyeball.

Macro targets are estimates. Adjust based on your weekly weight trend and how training feels. This is general information, not medical or dietary advice. Your inputs stay in your browser.