About CalorieMatrix

What is CalorieMatrix?

CalorieMatrix is a free online resource for health and fitness calculations. We provide tools to estimate daily calorie needs, macronutrient targets, body composition metrics, hydration requirements, training loads, and pregnancy-related dates — all backed by established formulas used in clinical and sports nutrition practice.

Our goal is to make reliable health math accessible without sign-up, paywalls, or confusing jargon. Every calculator includes plain-language explanations, formula transparency, and clear limitations so you can use the results as a starting point — not a prescription.

Who is it for?

Whether you are starting a fat-loss phase, planning muscle gain, tracking body composition, or simply curious about your numbers, CalorieMatrix gives you instant estimates in both English and Spanish. No account required.

Important disclaimer

All tools on this site are for informational and educational purposes only. They do not replace advice from a qualified physician, registered dietitian, or other healthcare professional. Always consult a professional before making significant changes to your diet, exercise, or medical care.