Fitness Calculators
Free online health and fitness tools with instant results
Whether you are trying to lose weight, build muscle, or maintain your current physique, having accurate numbers is the foundation of success. Our fitness calculators use proven scientific formulas to give you personalized targets for calories, macros, body composition, and more — all for free with instant results.
Sleep Calculator
Find the best times to wake up or go to sleep based on sleep cycles.
BMI Calculator
Calculate your Body Mass Index based on height and weight.
Calorie Calculator
Find your daily calorie needs based on age, activity, and goals.
Body Fat Percentage Calculator
Estimate your body fat percentage using the US Navy method.
Ideal Weight Calculator
Determine your ideal body weight using multiple formulas.
TDEE Calculator
Calculate Total Daily Energy Expenditure and macro split.
Macro Calculator
Calculate your daily macronutrient targets for cutting, bulking, or maintenance.
Protein Intake Calculator
Find your optimal daily protein intake by body weight and goal.
Calorie Deficit Calculator
Calculate your calorie deficit to lose 1 pound per week.
Lean Bulk Calculator
Calculate surplus calories and macros for lean muscle gain.
One Rep Max Calculator
Estimate your one-rep max from weight and reps performed.
Water Intake Calculator
Calculate how much water you should drink daily.
Running Pace Calculator
Calculate your running pace per mile or per kilometer.
Heart Rate Zone Calculator
Find your heart rate training zones using the Karvonen method.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio and health risk level.
VO2 Max Calculator
Estimate your VO2 max from a timed run or walk test.
Army Body Fat Calculator
Calculate body fat using the US Army tape measurement method.
Bench Press Standards Calculator
See how your bench press compares to strength standards.
BAC Calculator
Estimate blood alcohol content based on drinks, weight, and time.
Steps to Miles Calculator
Convert step count to miles or kilometers walked.
Fitness Guides & Articles
What is TDEE and How to Use It for Weight Loss
Learn what Total Daily Energy Expenditure (TDEE) means and how to use it effectively for sustainable weight loss.
How to Calculate Your Macros for Beginners
A beginner-friendly guide to calculating your macronutrient targets for weight loss, muscle gain, or maintenance.
Body Fat Percentage: What's Healthy for Your Age?
Discover healthy body fat percentage ranges for men and women at every age, and learn how to measure yours accurately.
The Difference Between BMR and TDEE Explained
Understand the key differences between BMR and TDEE, and why TDEE is more useful for planning your diet.
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Frequently Asked Questions
What fitness calculators do you offer?
We offer 15 free fitness calculators including TDEE, calorie, macro, body fat, BMI, protein intake, calorie deficit, lean bulk, one rep max, ideal weight, water intake, running pace, heart rate zone, waist-to-hip ratio, and sleep calculators. All produce instant results.
How accurate are your fitness calculators?
Our calculators use established formulas like the Mifflin-St Jeor equation and the US Navy body fat method. They provide reliable estimates within 5-10% for most people.
Do I need to create an account?
No account is needed. All calculators are completely free to use with instant results. You can share results via URL.
Which calculator should I use for weight loss?
Start with the TDEE Calculator to find your maintenance calories, then use the Calorie Deficit Calculator to determine how much to reduce for safe weight loss.
Can I use these calculators on my phone?
Yes, all calculators are fully mobile-optimized with touch-friendly inputs and numeric keyboards for number fields.