Macro Nutrient Calculator

The Macro Nutrient Calculator turns a daily calorie target into concrete grams of protein, carbohydrate and fat so you can plan meals against real numbers instead of vague percentages.

Enter the calories you want to eat each day — usually your TDEE adjusted for a cut, maintenance or bulk — then pick a macro split.

Four presets cover the most common approaches: balanced (30/40/30), low carb (35/25/40), high protein (40/35/25) and keto (25/5/70).

If none of those fit, switch to a custom split and type your own protein, carb and fat percentages; the tool checks that they add up to 100 before doing the maths.

Conversions use the standard Atwater factors, where protein and carbohydrate each provide 4 calories per gram and fat provides 9.

The result shows both the gram targets and the calories each macronutrient contributes, so you can sanity-check the split at a glance and adjust until it matches your training and preferences.

All calculation happens locally in your browser — no calories, body data or results are uploaded, logged or stored — so it is completely private and keeps working offline once the page has loaded.

Pair it with a TDEE estimate to build a full nutrition plan in a couple of minutes.