Macro Calculator

How to use

1. 1Pick an input mode: Calculate from body stats (age, sex, weight, height, activity) or I already know my TDEE (paste a calorie number).
2. 2Choose your goal: aggressive cut, mild cut, maintain, mild bulk, or aggressive bulk. The goal scales TDEE up or down.
3. 3Pick a macro split: Balanced 30/40/30, Low-carb, High-protein, Keto, Athlete, or Custom (your own protein/carbs/fat percentages).
4. 4Pick the number of meals per day. Read your daily protein, carbs, and fat in grams, the per-meal breakdown, and the protein density per kilogram or pound of body weight.
5. 5Use any Copy button for a single value, or click Copy summary for a paste-ready three-line summary.

About this tool

Macro Calculator turns a daily calorie target into protein, carbs, and fat in grams, scaled to your goal and macro split, and broken down per meal. Pick the input mode that matches you: 'Calculate from body stats' takes age, biological sex, weight, height, and activity level and computes BMR using the Mifflin-St Jeor equation (the most accurate of the common BMR formulas for healthy adults), then multiplies by the standard activity factor (1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 extra active) to give TDEE in kcal/day. 'I already know my TDEE' lets you paste a calorie number from your own tracking or from the TDEE Calculator and skips the body-stat inputs, with an optional weight field so the tool can still show protein per kilogram or pound of body weight. Pick a goal (aggressive cut at -20%, mild cut at -10%, maintain, mild bulk at +10%, or aggressive bulk at +15% of TDEE) and a macro split: Balanced 30/40/30 (USDA-style and good default), Low-carb 35/25/40, High-protein 40/40/20 (muscle building or aggressive cuts), Keto 25/5/70 (very low carb), Endurance/athlete 25/55/20 (higher carbs to fuel training), or Custom where you set protein, carbs, and fat percentages and the tool checks they sum to 100%. The math uses 4 kcal per gram of protein and carbs and 9 kcal per gram of fat to convert each share of daily calories into grams. The result panel shows your daily target calories, daily protein, carbs, and fat in grams (each with kcal and %), a colored bar that visualizes the calorie split, protein density per kilogram and per pound of body weight (a useful sanity check: 1.2 to 1.6 g/kg for general health, 1.6 to 2.2 g/kg for muscle gain or fat loss), the per-meal breakdown for 3, 4, 5, or 6 meals/day so you can plan portions, and a one-click 'Copy summary' that gives you a paste-ready three-line summary for a notes app, training log, or message. A unit toggle preserves your numbers between metric (kg, cm) and imperial (lb, ft + in), four sample profiles seed realistic cutting, bulking, maintenance, and keto setups, and a macro split reference card explains each preset side by side. The calculator runs entirely in your browser, so the calorie target, weight, height, age, and dietary choices you enter never leave your device. Useful for planning a fat-loss phase after running the TDEE Calculator, sizing a lean bulk for muscle gain, picking a starting protein number that respects body weight, comparing how a balanced split versus keto changes your grams, building a meal plan from a daily target, or just answering 'how many grams of protein and carbs should I eat per day' with a real formula. Macro targets are population-level estimates for healthy adults aged 14 and up, not medical or nutrition advice. Real daily needs vary with body composition, activity accuracy, hormones, sleep, and the thermic effect of food, so use the number as a starting point, weigh yourself weekly, and adjust based on actual results. Talk to a qualified medical or nutrition professional during pregnancy or breastfeeding, or for any health condition.

Free to use. Works in your browser. No signup, no login.