Free Calculator Tools for Endurance Athletes
Optimize your training with our comprehensive suite of calculators for runners, cyclists, and triathletes. Get instant results for heart rate zones, pace, power, and more.
❤️ Heart Rate & Training Zones
Calculate your optimal training zones for maximum performance and recovery
Zone 2 Calculator
Find your aerobic base training zone for optimal endurance development
Heart Rate Zone Calculator
Calculate all 5 training zones based on your maximum heart rate
Max Heart Rate Calculator
Determine your maximum heart rate using multiple proven formulas
Target Heart Rate Calculator
Find your target heart rate for specific workout intensities
Karvonen Formula Calculator
More accurate heart rate zones using your resting heart rate
🏃 Running Calculators
Pace, race time prediction, and performance tools for runners
Running Pace Calculator
Calculate pace, time, and distance for your runs
Race Time Predictor
Predict race times based on recent performance or VO2 max
Run-Walk Calculator
Optimize your run-walk intervals for marathon training
Calories Burned Running
Calculate calories burned during your running workouts
Mile to KM Converter
Convert between miles and kilometers for running distances
Treadmill Pace Converter
Convert between treadmill speed (mph/kph) and running pace
🚴 Cycling Calculators
Power, gearing, and performance tools for cyclists
Bike Gearing Calculator
Calculate gear ratios and development for optimal performance
Cadence Speed Calculator
Find your speed based on cadence and gear selection
Power-to-Weight Ratio
Calculate your power-to-weight ratio for cycling performance
FTP Calculator
Determine your Functional Threshold Power from test results
Watts to Calories Calculator
Convert power output to calories burned during cycling
🎽 VO2 Max & Fitness
Assess and track your cardiovascular fitness and performance
VO2 Max Calculator
Estimate your VO2 max from running performance data
Cooper Test Calculator
Calculate VO2 max from 12-minute run test results
Lactate Threshold Calculator
Determine your lactate threshold pace and heart rate
Aerobic vs Anaerobic Threshold
Calculate both aerobic and anaerobic threshold values
🔧 Utility & Conversion Tools
Quick conversion tools and utility calculators for training
BPM to % Max Calculator
Convert heart rate BPM to percentage of maximum
Pace to Speed Converter
Convert running pace (min/mile) to speed (mph)
Speed to Pace Converter
Convert speed (mph/kph) to running pace
Min/Mile to KPH
Convert minutes per mile pace to kilometers per hour
KPH to Min/Mile
Convert kilometers per hour to minutes per mile pace
Calories per Hour
Calculate hourly calorie burn for various activities
Sweat Test Calculator
Determine your fluid replacement needs and optimal hydration strategy
Why Choose RunBikeCalc?
Mobile Optimized
All calculators work perfectly on your phone, tablet, or desktop
Instant Results
Get immediate calculations with real-time updates as you type
Always Free
No registration required. All tools are completely free to use