Health & Fitness
Macro Calculator
Macro Calculator is a browser-based calculator tool on CalcToolsBase. Turn a daily calorie target into grams of carbohydrate, protein, and fat for your chosen split. To use it, enter your values and view the result directly in your browser — no signup and nothing to install.
Macro Calculator turns your daily calories and macro split into grams of carbs, protein and fat per day using your calorie target split into carbs, protein and fat. The maths runs locally, so nothing you enter leaves the page.
About this calculator
Macro Calculator is built to work out your macros without a server round-trip. Provide your daily calories and macro split and it uses your calorie target split into carbs, protein and fat to produce grams of carbs, protein and fat per day, instantly and entirely in your browser, which makes it handy for quick checks and repeat runs.
Macro splits are a framework, not a rule. Protein needs scale with body weight and goals, and the best split is the one you can follow consistently — adjust as needed.
How to use
- Enter your daily calorie target.
- Choose a macro split such as balanced, low carb, high protein, or keto.
- Press Calculate to see grams of carbs, protein, and fat.
- Adjust the split if it does not fit your routine.
Why use Macro Calculator
Fast
Calculations run in your browser. No round trip to a server.
Private
Your inputs never leave your device. Nothing is uploaded.
Free
No signup, no paywall, no ads-in-results, no watermarks.
Educational
Uses common estimation formulas for educational purposes. Results are not medical advice and should not replace professional guidance.
Mobile-ready
Optimised for phones, tablets, and desktops alike.
Transparent
Clear about formulas used and their limits, with disclaimers where they matter.
Common uses
Macro for setting realistic training goals
Macro for everyday fitness check-ins
Macro when logging weekly numbers
Macro for gym and home-workout planning
Macro in personal-training sessions
Macro for comparing before-and-after
Technical notes
Macro Calculator splits your daily calories into protein, carbohydrate and fat (4, 4 and 9 kcal per gram) by the ratio you choose.
These are general-population estimates and not a substitute for advice from a qualified clinician.
Nothing you type is uploaded — the calculation happens entirely on your device.
FAQ
How are macro grams calculated?
Each macro’s calorie share is divided by its energy density: 4 kcal/g for carbohydrate and protein, 9 kcal/g for fat. For 2000 kcal balanced, that is 250 g carbs, 125 g protein, 56 g fat.
What do the split presets mean?
Balanced is 50/25/25, low carb is 20/40/40, high protein is 40/40/20, and keto is 5/25/70, written as carbohydrate / protein / fat.
Which split is best?
It depends on goals and preference. Higher protein supports muscle retention, while keto minimises carbs — consistency usually matters more than the exact ratio.
Does the Macro Calculator send my data to a server?
No. The Macro Calculator runs entirely in your browser — your inputs never leave your device, and nothing is uploaded or stored.
Worked example
On a 2,000-kcal day with 30% protein / 40% carbs / 30% fat: 150 g protein, 200 g carbs and 67 g fat (protein & carbs = 4 kcal/g, fat = 9 kcal/g). Estimates only.