Essential Fitness & Health Calculators
All-in-one fitness calculator hub with science-backed tools to calculate BMI, BMR, macros, calories, strength, and more. Track your progress with precision.
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Body Metrics
Calculators for body composition and size.
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Calories & Energy
Determine your daily energy needs.
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Macronutrients
Balance your protein, carbs, and fats.
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Strength
Calculators for strength training and performance.
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Cardio
Tools for cardiovascular fitness and endurance.
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Health & Wellness
Calculators for overall well-being.
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Featured Calculators
BMI Calculator
Calculate your Body Mass Index.
TDEE Calculator
Estimate your Total Daily Energy Expenditure.
1RM Calculator
Estimate your one-rep max for any lift.
Macro Split Calculator
Determine your optimal macronutrient split.
Body Fat % (U.S. Navy)
Estimate body fat using the U.S. Navy method.
Protein Intake Calculator
Determine your daily protein needs.
Calorie Deficit
Calculate the deficit needed for weight loss.
Heart Rate Zones
Calculate your target heart rate zones for training.
Why FitCalcStack?
We replace guesswork with clear, actionable insights to help you set realistic goals and track meaningful progress.
Accurate & Science-Based
Every calculator is built on peer-reviewed formulas and established industry standards to ensure reliable results.
Simple & Free to Use
Our tools are intuitive, completely free, and provide clear explanations of what the results mean for you.
For Every Fitness Level
Whether you're a beginner or a seasoned athlete, our calculators are designed to give you the data you need to succeed.