Resources
Science-based guides to help you train and eat smarter.
Guides
Articles & guides
In-depth answers on calories, macros, body composition, training, and more.
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Free calculators
Thirteen science-backed tools for instant estimates — TDEE, macros, heart rate zones, and more.
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CalorieMatrix organizes articles and tools around the questions people ask most about nutrition, training, and body metrics. Start with a guide below, or jump straight to our calculators when you need a number.
- Calories & TDEE: Daily energy needs, deficits, and weight-change planning.
- Macros: Protein, carbs, and fat targets for your goal.
- Body composition: BMI, body fat percentage, lean mass, metabolic age.
- Cardio & activity: Heart rate zones and calories burned by exercise.
- Sleep & recovery: Optimal bedtime and wake times by sleep cycle.
- Hydration: Daily water intake estimates.
- Strength: One-rep max and training percentages.
- Pregnancy & fertility: Due dates and ovulation windows.