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Free Fitness Calculators for Every Goal

Precision tools trusted by personal trainers, athletes, and fitness enthusiasts. Calculate BMI, macros, one-rep max, TDEE, and 40+ more metrics—all 100% free.

45+ Free Calculators
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Body Composition Calculators

Understand your body metrics including BMI, body fat percentage, and lean mass

Body

BMI Calculator

Calculate your Body Mass Index to assess if your weight is healthy for your height using the standard BMI formula.

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Nutrition & Diet Calculators

Calculate calories, macros, and optimize your nutrition for any fitness goal

Nutrition

TDEE Calculator

Calculate your Total Daily Energy Expenditure to understand how many calories you burn daily based on activity level.

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⭐ Premium Nutrition

BMR Calculator

Calculate your Basal Metabolic Rate—the calories your body needs at complete rest for basic life functions.

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Strength Training Calculators

Maximize your lifts with rep max calculators and training programming tools

Cardio & Endurance Calculators

Track cardiovascular fitness, pace, and endurance training metrics

Specialized Calculators

Military fitness tests, athletic performance, and specialized assessments

The Complete Guide to Fitness Calculators

Understanding your body's metrics is the foundation of any successful fitness journey. Whether you're trying to lose weight, build muscle, improve athletic performance, or simply maintain optimal health, having accurate data about your body composition, nutritional needs, and training capacity is essential.

Why Fitness Calculators Matter

Generic fitness advice rarely works because every body is different. A 6-foot-2 athlete with 15% body fat has vastly different caloric needs than a 5-foot-4 office worker at 30% body fat. Our fitness calculators eliminate guesswork by providing personalized recommendations based on your unique metrics.

Body Composition Calculators help you understand what you're made of. Your BMI gives a quick snapshot of weight-to-height ratio, but body fat percentage and lean body mass tell the real story. Our calculators use validated formulas like the Navy method and Jackson-Pollock equations to estimate these crucial metrics.

Nutrition Calculators take the confusion out of eating for your goals. Your TDEE (Total Daily Energy Expenditure) is the starting point—once you know how many calories you burn, you can adjust intake for fat loss or muscle gain. Our macro calculator then breaks this into optimal protein, carbohydrate, and fat targets.

Strength Training Calculators optimize your programming. Knowing your one-rep max allows you to train at precise percentages for strength, hypertrophy, or power. The Wilks Score helps competitive lifters compare performance across weight classes.

Cardio & Endurance Calculators improve cardiovascular training efficiency. Training in the right heart rate zone—whether for fat oxidation, aerobic development, or anaerobic threshold—requires knowing your personal zones based on max heart rate and VO2 max.

How to Get the Most Accurate Results

  • Take measurements in the morning before eating, after using the bathroom, for most consistent body composition readings.
  • Use a flexible tape measure for circumference measurements, keeping the tape parallel to the floor.
  • Be honest about activity level when calculating TDEE—overestimating activity is the most common error.
  • Recalculate every 4-6 weeks as your body changes from training and nutrition adjustments.
  • Use multiple calculators together for a complete picture—BMI alone doesn't tell the whole story.

Understanding Your Results

Numbers are meaningless without context. Our calculators include reference ranges based on age, sex, and fitness level. A "good" VO2 max for a 50-year-old is different from a 25-year-old athlete. Similarly, optimal macro ratios vary based on training style—endurance athletes need more carbs than powerlifters.

Remember that calculators provide estimates based on population averages. Individual variation exists, so use these tools as starting points and adjust based on real-world results. Track your progress, reassess regularly, and refine your approach over time.

Frequently Asked Questions

Expert answers to common fitness calculation questions

DEXA scans are the gold standard for body fat measurement, but for home use, the Navy Body Fat Calculator using circumference measurements provides reasonable accuracy. Our calculator uses the U.S. Navy formula, which has been validated in clinical studies to be within 3-4% of hydrostatic weighing results for most individuals.
Your Total Daily Energy Expenditure (TDEE) is calculated by multiplying your Basal Metabolic Rate (BMR) by an activity factor. Use our TDEE Calculator to get your maintenance calories, then subtract 300-500 calories for sustainable weight loss. A deficit larger than 500 calories may lead to muscle loss and metabolic adaptation.
One-rep max standards vary by exercise and body weight. For bench press, beginners typically achieve 0.5-0.75x body weight. Use our 1RM Calculator with submaximal weights (5-10 reps) to safely estimate your max without the injury risk of actual max attempts. The Epley formula we use is accurate within 5% for most lifters.
For lean muscle gain, eat 200-300 calories above your TDEE (maintenance calories). Our Calorie Surplus Calculator helps you find this target while minimizing fat gain. Aim for 0.25-0.5 lbs of weight gain per week, with protein intake of 0.7-1g per pound of body weight.
While Zone 2 (60-70% max heart rate) burns the highest percentage of fat as fuel, total calorie burn matters more for fat loss. Our Heart Rate Zones Calculator shows all five zones. For optimal results, combine Zone 2 training with higher-intensity intervals for maximum calorie expenditure.
BMI calculations are mathematically precise (weight in kg ÷ height in m²), but BMI itself has limitations. It doesn't distinguish between muscle and fat mass, making it less accurate for athletes. Use our BMI Calculator alongside body fat percentage and waist-to-hip ratio for a complete picture of body composition.
The Wilks Score is a coefficient used in powerlifting to compare lifters across different weight classes. It adjusts your total (squat + bench + deadlift) relative to body weight. Our Wilks Calculator helps competitive lifters see how they stack up. A score above 300 is considered intermediate, while 400+ is advanced.
Macro ratios depend on your goal: For fat loss, try 40% protein, 30% carbs, 30% fat. For muscle gain, use 30% protein, 45% carbs, 25% fat. For maintenance, 30% protein, 40% carbs, 30% fat works well. Our Macro Calculator customizes these ratios based on your specific metrics and activity level.

Explore all free calculators on Clickzy to make smarter, data-driven fitness decisions.

On our Body Composition Calculators page, the Jackson-Pollock Body Density Calculator helps provide a more accurate picture of your fitness by estimating body fat percentage from skinfold measurements.

Unlike BMI alone, this method focuses on body composition, supporting more informed decisions about fat loss, muscle gain, and overall health tracking.