Fitness & Training Calculators
Data-driven fitness calculators for lifters, runners, and anyone tracking their training. One-rep max estimates, pace calculators, calorie burn rates, body composition analysis, and programming tools.
- ✓Strength: one-rep max, Wilks score, bench/squat/deadlift
- ✓Cardio: pace, race time prediction, heart rate zones, VO2 max
- ✓Body composition: body fat, FFMI, lean mass, army body fat
- ✓Nutrition: calories burned, weight loss projections, muscle gain
Most used: One Rep Max Calculator, Pace Calculator, Calories Burned Calculator
Try any of the 22 fitness & body calculators below — or get one free for your AI.
Every calculator on this page is free to use right now. You can also download any one as a Claude skill file (free with email) to chat with it in Claude Code, ChatGPT, or any AI platform. Or get the full Fitness & Training Pack for $29.
Common workflows in this category
Click any scenario to jump into the calculator with the example pre-loaded.
22 free calculators
Army Body Fat Calculator
Calculate body fat percentage using the Army formula. Determine if you meet military fitness standards.
Bench Press Calculator
Calculate bench press standards by bodyweight and experience level. Estimate your one-rep max from any lift count.
Body Recomposition Calculator
Calculate your deficit and surplus for body recomposition. Learn how to improve body composition without gaining or losing weight.
Calories Burned Calculator
Calculate calories burned during exercise by activity, duration, and intensity. Works for running, cycling, swimming, and 100+ activities.
Cycling Calories Calculator
Calculate calories burned cycling. Accounts for bike type, speed, and terrain to estimate your calorie expenditure.
Deadlift Calculator
Calculate deadlift standards by bodyweight and experience. Estimate your one-rep max and compare to realistic benchmarks.
FFMI Calculator
Calculate your FFMI (fat-free mass index) to assess natural muscular potential and body composition.
Max Heart Rate Calculator
Calculate your maximum heart rate and training zones. Uses both traditional and Tanaka formulas for accuracy.
Muscle Gain Calculator
Estimate how much muscle you can realistically gain per month based on training experience and genetics.
One Rep Max Calculator
Calculate your one-rep max from any rep range. Works with Epley and Brzycki formulas for accurate strength estimates.
Pace Calculator
Calculate pace per mile/km from your goal time and race distance. Perfect for marathon, half-marathon, and 5K race planning.
Race Time Predictor
Predict race times at different distances based on your current race time. Plan training for marathons, half-marathons, 5Ks.
Rest Period Calculator
Calculate ideal rest periods between sets based on your training goal: strength, hypertrophy, or endurance.
Running Speed Calculator
Calculate running speed in mph or km/h from your pace. Instantly convert between minutes per mile and miles per hour.
Squat Calculator
Calculate squat standards by bodyweight and experience. See what's a good, competitive, and elite squat for your weight.
Steps to Miles Calculator
Convert steps to miles accurately. Account for stride length, height, and pace to see your real walking distance.
Swimming Calories Calculator
Calculate calories burned swimming. Works for all strokes: freestyle, backstroke, breaststroke, butterfly, and mixed workouts.
VO2 Max Calculator
Calculate your estimated VO2 max from running tests. Understand your aerobic fitness level and cardiovascular capacity.
Walking Calories Calculator
Calculate calories burned walking. Account for speed, terrain, and body weight to estimate your calorie expenditure.
Warm-Up Weight Calculator
Calculate appropriate warm-up weights for your heavy lift. Progressive warm-up routine based on your working weight.
Weight Loss Calculator
Calculate how long it takes to lose pounds at your calorie deficit. Plan realistic timelines for your weight loss goal.
Wilks Score Calculator
Calculate your Wilks coefficient to compare your total strength across weight classes and genders in powerlifting.