Macro Calculator

Your daily targets come in two parts. Protein is set first, directly from your body weight and goal, since protein needs are tied to body size rather than total calories. Fat and carbohydrate then split whatever calories are left, shown as a few different balances so you can pick whichever fits how you actually like to eat, rather than one arbitrary ratio applied to everyone.

What This Calculator Measures

This gives you a full daily target: calories, a protein range based on your body weight and goal, and up to three fat/carbohydrate pairings so you can see how your remaining calories can be split without picking a preference in advance.

The Formula

Target calories = BMR × activity multiplier ± your goal’s calorie adjustment. BMR is estimated using the Mifflin-St Jeor equation¹, the most widely validated resting-energy formula in current use. Protein and carbohydrate both provide about 4 calories per gram, and fat provides about 9².

Daily protein (g) = weight or lean body mass (kg) × target g/kg, chosen by goal

Fat (g) = target g/kg × weight (kg); Carbs (g) = (target calories − protein calories − fat calories) ÷ 4

How This Calculator Computes Your Result

Enter your stats, activity level, and goal above. We calculate your target calories first, then set your protein range using the same tiered logic as the Protein Calculator, then compute up to three fat/carbohydrate pairings (Lower Carb, Balanced, and Higher Carb) from whatever calories remain once protein is set.

Setting Your Calorie Target

Your goal sets a calorie adjustment from maintenance: no change for Maintain Weight, ±250 kcal/day for a mild pace, ±500 kcal/day for a standard pace, or −1,000 kcal/day for Aggressive Loss (roughly 0.5, 1, or 2 lb/week using the standard ~3,500-kcal-per-pound approximation).

We always show your actual calculated number, and we never substitute a different one. If your result falls below 1,200 kcal/day (women) or 1,500 kcal/day (men), the low end of the range cited in the 2013 AHA/ACC/TOS Obesity Guideline for supervised low-calorie diets³, we show a note rather than changing your number: intake that low is generally recommended only with medical supervision.

Setting Your Protein Target

Protein is set from your body weight, or lean body mass if you enter your body fat percentage, using the same tiers as the Protein Calculator:

• Any weight-loss goal: 2.3–3.1 g/kg lean body mass, or 1.6–2.2 g/kg bodyweight if body fat % isn’t provided⁴. Protein needs rise during a deficit to help protect muscle.

• Maintaining weight, sedentary: 0.8 g/kg under 65, 1.0–1.2 g/kg for 65 and older²,⁵.

• Maintaining weight, any other activity level: 1.4–2.0 g/kg⁶.

• Any weight-gain goal: 1.6–2.2 g/kg⁷.

Fat and Carbohydrates

Once protein and your calorie target are set, whatever’s left splits between fat and carbohydrate. Unlike protein, there’s no single body-weight target the evidence points to here, so instead of picking one number for you, this calculator shows three practical balances: Lower Carb (higher fat, ~1.0 g/kg bodyweight), Balanced (~0.8 g/kg), and Higher Carb (lower fat, ~0.6 g/kg).

All three use the exact same protein and calorie numbers, only how the remainder is split changes. This part is genuinely about what you can sustain day to day, not a target to hit precisely, so pick whichever set of numbers looks like food you’d actually eat. If your protein target leaves little or no room for one or more of these, only the options that fit are shown, with a note explaining why.