Macro Calculator
Calculate your daily macronutrient targets online for free with our macro calculator. Enter your age, sex, weight, height, and activity level, select your goal — cut, bulk, or maintain — and choose a macro split preset to get your daily protein, carbs, and fat targets in both grams and calories. Supports four presets and a fully custom split. No signup required — all calculations run locally in your browser.
Enter your stats, select your goal and macro split, then click Calculate. Our macro calculator uses the Mifflin-St Jeor equation to compute your TDEE, applies your goal calorie adjustment, and splits the result into daily protein, carbs, and fat targets in both grams and calories. All calculations run instantly in your browser — no signup required.
Why Use Our Macro Calculator?
Instant Macro Calculations
Calculate your daily protein, carbs, and fat targets instantly in your browser. Our macro calculator uses the Mifflin-St Jeor equation to compute your TDEE, applies your goal adjustment, and splits the result into macros in milliseconds.
Secure Macro Calculator Online
All macro calculations run locally in your browser. Your age, weight, height, and body stats never leave your device, ensuring 100% privacy every time you use our macro calculator online.
Macro Calculator - No Installation
Use our macro calculator directly in any browser with no downloads, plugins, or software required. Calculate your macronutrient targets from any device, completely free.
Five Goals & Four Macro Presets
Our macro calculator supports five goals (aggressive cut to aggressive bulk) and four macro split presets — balanced, high protein, low carb, and high carb — plus a fully custom split where you enter your own percentages.
Common Use Cases for Macro Calculator
Fat Loss & Cutting
Use our macro calculator with the "Moderate Cut" or "Aggressive Cut" goal to get precise daily protein, carbs, and fat targets for a calorie deficit. The high-protein preset helps preserve muscle mass during a cut.
Muscle Gain & Bulking
Bodybuilders and athletes use our macro calculator with the "Lean Bulk" or "Aggressive Bulk" goal to calculate the exact macros needed for muscle growth. The high-protein preset ensures adequate protein for muscle protein synthesis.
Maintenance & Body Recomposition
Use our macro calculator with the "Maintain Weight" goal and a high-protein split to support body recomposition — losing fat while gaining muscle simultaneously at maintenance calories.
Endurance & Athletic Performance
Endurance athletes use our macro calculator with the "High Carb" preset to maximise glycogen stores for training and competition. The macro calculator shows exact carbohydrate grams needed to fuel high-volume training.
Low-Carb & Ketogenic Diets
Use our macro calculator with the "Low Carb" preset to calculate macros for a low-carbohydrate or ketogenic approach. The custom split option lets you set carbs as low as 5% for strict keto protocols.
Meal Planning & Tracking
Nutrition coaches and meal planners use our macro calculator to set daily targets for clients. The full breakdown showing grams and calories for each macro makes it easy to build meal plans that hit exact targets.
Understanding Macro Calculations
What is a Macro Calculator?
A macro calculator computes your daily macronutrient targets — the grams of protein, carbohydrates, and fat you should eat each day to support your specific goal. The calculation starts with your TDEE (Total Daily Energy Expenditure), which is your BMR multiplied by an activity factor. A goal-based calorie adjustment is then applied (e.g. −500 kcal for a moderate cut), and the resulting target calories are split into macros using your chosen percentage split. Our macro calculator uses the Mifflin-St Jeor equation for BMR, supports five goals and four macro presets, and shows results in both grams and calories — all running locally in your browser with no data sent to any server.
How Our Macro Calculator Works
- 1. Enter Your Stats and Select Your Goal: Enter your age, sex, weight, and height, then select your activity level and goal — from aggressive cut (−1000 kcal) to aggressive bulk (+500 kcal). The macro calculator uses the Mifflin-St Jeor equation to compute your TDEE and applies the goal adjustment to get your target calories.
- 2. Choose a Macro Split Preset: Select from four presets — Balanced (30/40/30), High Protein (40/35/25), Low Carb (35/15/50), or High Carb (25/55/20) — or choose Custom to enter your own protein, carbs, and fat percentages. The percentages must total 100%.
- 3. View Your Daily Macro Targets: Click Calculate Macros to see your daily protein, carbs, and fat targets in both grams and calories, with a visual macro bar, protein-per-kg reference, and a full breakdown table showing every calculation step.
What Each Macronutrient Does
- Protein — 4 kcal/g: Protein is essential for muscle repair, immune function, and satiety. The recommended intake for active adults is 1.6–2.2 g per kg of bodyweight. Higher protein intakes (up to 2.5 g/kg) are beneficial during a calorie deficit to preserve muscle mass.
- Carbohydrates — 4 kcal/g: Carbohydrates are the body's primary fuel source, especially for high-intensity exercise. They are stored as glycogen in muscles and the liver. Higher carb intakes support performance in endurance and strength training.
- Fat — 9 kcal/g: Dietary fat is essential for hormone production, fat-soluble vitamin absorption (A, D, E, K), and cell membrane integrity. Fat provides 9 kcal per gram — more than double protein or carbs — so small changes in fat grams have a large calorie impact.
- Goal Calorie Adjustments: A deficit of 500 kcal/day produces approximately 0.5 kg of fat loss per week (3,500 kcal ≈ 0.45 kg fat). A surplus of 300–500 kcal/day supports lean muscle gain. Aggressive deficits (−1000 kcal) risk muscle loss without adequate protein.
What the Macro Calculator Shows
- BMR & TDEE: Your Basal Metabolic Rate and Total Daily Energy Expenditure, calculated using the Mifflin-St Jeor equation.
- Target Calories: Your TDEE adjusted for your selected goal — from aggressive cut to aggressive bulk.
- Macro Targets in Grams: Daily protein, carbs, and fat in grams, calculated from your target calories and chosen split.
- Macro Targets in Calories: The calorie contribution of each macro, so you can verify the split adds up correctly.
- Protein per kg: Your protein target expressed per kilogram of bodyweight, compared against the recommended 1.6–2.2 g/kg range for active adults.
Related Tools
Voice Recorder & Audio Extractor
Record high-quality audio from your microphone or extract audio from MP4 and WebM video files offline. 100% secure, browser-based utility.
Audio Slicer & Converter
Trim audio clips and convert between MP3, WAV format client-side - Free online audio cutter
ID3 Tag & Metadata Editor
Read and write ID3 tags, album art, artist, and track details directly to MP3 file headers - Free online ID3 tag editor
MP3 Metadata Viewer
View all ID3 tags — title, artist, album, artwork, BPM, and every embedded frame — from any MP3 file instantly in your browser - Free online MP3 metadata viewer
Frequently Asked Questions About Macro Calculator
A macro calculator computes your daily macronutrient targets — the grams of protein, carbohydrates, and fat you should eat each day to support your specific goal. Our macro calculator uses the Mifflin-St Jeor equation to calculate your TDEE, applies a goal-based calorie adjustment, and splits the result into macros using your chosen percentage split — all running instantly in your browser.
Macros (macronutrients) are the three main nutrients that provide calories: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Tracking macros rather than just calories gives you more control over body composition — you can lose fat while preserving muscle by keeping protein high, or optimise performance by adjusting carbohydrate intake.
For active adults, the evidence-based recommendation is 1.6–2.2 g of protein per kg of bodyweight per day. During a calorie deficit, higher protein intakes (up to 2.5 g/kg) help preserve muscle mass. Our macro calculator shows your protein-per-kg ratio so you can verify it falls within the recommended range.
Balanced (30/40/30) is a general-purpose split suitable for most goals. High Protein (40/35/25) maximises muscle preservation and satiety, ideal for cutting. Low Carb (35/15/50) reduces carbohydrates for ketogenic or low-carb approaches. High Carb (25/55/20) maximises glycogen for endurance athletes. The Custom option lets you set your own percentages.
The macro calculator applies a calorie adjustment to your TDEE based on your goal: Aggressive Cut (−1000 kcal), Moderate Cut (−500 kcal), Maintain (0 kcal), Lean Bulk (+300 kcal), Aggressive Bulk (+500 kcal). A deficit of 500 kcal/day produces approximately 0.5 kg of fat loss per week. The minimum target is 1,200 kcal/day.
Absolutely. Our macro calculator runs entirely in your browser. Your age, weight, height, sex, and all other inputs are never sent to any server or tracked in any way. Everything stays completely private on your device.
Yes — our macro calculator is 100% free with no signup, no account, no premium tier, and no usage limits. Calculate your macros as many times as you need, completely free forever.
The Mifflin-St Jeor equation is accurate to within ±10% for most people. Use your macro targets as a starting point, track your intake for 2–3 weeks, and adjust based on real-world results. If you are not losing or gaining weight as expected, adjust your target calories by 100–200 kcal.
Yes — select "Custom" from the Macro Split Preset dropdown and enter your own protein, carbs, and fat percentages. The percentages must total 100%. This is useful for specific dietary protocols like ketogenic (very low carb), carnivore (very high protein/fat), or any other approach not covered by the presets.