Macro Calculator
Turn your calorie target into daily protein, carb, and fat grams. Pick a goal and a diet style. Instant, private, free forever.
How to Use the Macro Calculator
Enter your stats the same way you would for a TDEE calculator, pick cut, maintain, or bulk, then pick a diet style. The calculator first works out your calorie target with the Mifflin-St Jeor formula, then splits those calories into protein, carb, and fat grams based on the diet style you picked. Change any field and the grams update immediately.
Worked example: a 35-year-old man, 5'9" (175 cm), 165 lb (75 kg), moderately active, cutting, on a Balanced split. TDEE comes out to 2,594 cal/day; a 20% cut puts his target at 2,075 cal/day. Balanced splits 30% protein / 40% carbs / 30% fat, so his targets are 156g protein, 208g carbs, and 69g fat — 2,075 calories, give or take rounding. Read our guide: how to calculate macros.
Why Macros Matter More Than Just Calories
Calories decide whether you gain, lose, or hold weight. Macros decide what that weight is made of, how hungry you feel along the way, and how much energy you have to train. Two people eating the identical 2,000 calories a day can end up in very different places if one eats mostly protein and vegetables and the other eats mostly sugar: same calorie math, different hunger, different muscle retention, different results on the scale after a few months.
The Four Diet Styles, Explained
| Style | Protein | Carbs | Fat | Best for |
|---|---|---|---|---|
| Balanced | 30% | 40% | 30% | General health, sustainable long-term |
| High Protein | 40% | 30% | 30% | Cutting, preserving muscle on a deficit |
| Low Carb | 35% | 20% | 45% | Steadier energy, less appetite swings |
| Keto | 20% | 5% | 75% | Strict carb restriction, ketosis |
Protein and carbs both supply 4 calories per gram; fat supplies 9. That is why a high-fat split like keto looks small in percentage terms on paper but still accounts for most of your calories — fat is more than double the energy density of the other two. None of these four is objectively "best": they are different tools for different goals and different levels of tolerance for restriction. Balanced is the easiest to sustain for most people; high protein earns its keep specifically during a cut.
How Much Protein Do You Actually Need?
Sports nutrition research generally supports 0.7 to 1 gram of protein per pound of bodyweight for people trying to build or preserve muscle, with some benefit up to about 1.2g/lb during an aggressive cut. These presets are percentages of calories, not fixed bodyweight ratios, so where they land in g/lb moves with both your calorie target and your weight — the note under your results shows your actual number. A bigger calorie target (bulking) or a lighter bodyweight will push the g/lb figure higher for the same percentage; a calorie deficit or a heavier bodyweight pulls it lower. If your number comes out well below 0.7g/lb, Low Carb or High Protein will close the gap. Landing above 1.2g/lb isn't harmful for most people with normal kidney function, it just isn't buying you extra muscle beyond that point.
What the Calculator Misses
This tool inherits the same accuracy range as any TDEE-based calculator: calorie estimates run 10 to 20% off for a given individual, since they are built from population averages and cannot see your muscle mass, genetics, or day-to-day activity outside formal exercise. The macro split itself is a starting ratio, not a medical prescription — people with kidney disease, diabetes, or other metabolic conditions should get a macro target from a doctor or registered dietitian, not a generic calculator. Use the numbers here as a two-to-three-week starting point, then adjust based on your energy, hunger, and progress.
Who Uses a Macro Calculator
Lifters use it to hit a protein target while cutting so the weight they lose is fat, not muscle. People newer to tracking use it to understand what "eat more protein" actually means in grams at breakfast, lunch, and dinner. Low-carb and keto dieters use it to find the carb ceiling that keeps them in their chosen range without guessing. Whatever the goal, grams on a plate are easier to act on than a single calorie number.
Frequently Asked Questions
What are macros?
Macros (macronutrients) are the three nutrients that supply calories: protein and carbohydrates each provide 4 calories per gram, and fat provides 9 calories per gram. Hitting a calorie target controls whether you gain or lose weight; splitting those calories into a macro ratio controls body composition, energy, and how full you feel.
How is a macro calculator different from a calorie calculator?
A calorie calculator (like a TDEE calculator) tells you how many total calories to eat. A macro calculator takes that same calorie number and splits it into grams of protein, carbs, and fat based on a diet style, so you know what to actually put on the plate, not just a single number.
How much protein do I need per day?
These presets are percentages of calories, not fixed bodyweight ratios, so the grams-per-pound they produce depends on your calories and weight — check the live number under your results. As a reference point, sports nutrition research generally supports 0.7 to 1.2 grams per pound of bodyweight for building or preserving muscle; if your result lands well below that, Low Carb or High Protein will close the gap.
What is a good macro split for weight loss?
Any split works for weight loss as long as total calories are in a deficit; macros mainly affect hunger, energy, and muscle retention, not the scale directly. A higher-protein split (35 to 40% of calories) is the most evidence-backed choice for a cut since it preserves muscle and keeps you fuller on fewer calories.
Is keto the same as low-carb?
No. Low-carb here means roughly 20% of calories from carbs, light but not restrictive. Keto is far stricter, around 5% of calories from carbs (commonly under 50g per day), which is low enough to shift the body into ketosis. Keto is harder to sustain and not required for fat loss.
Is this macro calculator free?
Yes, 100% free with no signup. Every calculation happens instantly in your browser and your numbers are never sent to a server.
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Want the full breakdown?
Why macros matter beyond the calorie number, the four diet styles compared, and how much protein you actually need.
Read the Macro Guide