Macro Calculator — Calories to Protein Carb Fat Grams

Calculate daily macro grams from calories and protein/carb/fat percents (4 / 4 / 9 kcal per gram). Example: 2000 kcal at 30/40/30% → 150 g / 200 g / ≈66.67 g. Educational only — not medical advice.

How it works

Enter daily calories and protein/carb/fat percents. This is textbook energy arithmetic, not a meal plan.

Formula

g_P = kcal×p%/4; g_C = kcal×c%/4; g_F = kcal×f%/9. Notes:

Percents must sum to 100 (± tiny float).
Not individualized nutrition therapy.
Pair with heart-rate / BMR–TDEE tools for education.

Example

Example: 2000 kcal at 30/40/30% → 150 g protein, 200 g carbs, ≈66.67 g fat.

When to use it

Classroom macro math.
Compare percent splits.
Educational pairing with BMR/TDEE.

Frequently asked questions

Sample?

2000 @ 30/40/30 → 150/200/≈66.67 g.

Medical advice?

No — educational only.

Why 9 for fat?

Fat has ~9 kcal/g; P/C ~4.

Sum ≠100?

Rejected.

Important notice

Educational macronutrients only — not medical advice. Consult a qualified clinician.

References: CDC / ACSM-style educational references.

Questions or feedback

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