Category
Cardio & Endurance Calculators
Free cardio calculators for heart rate zones, VO2 max, running pace, steps to calories, and more. Optimize your endurance training with science.
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Heart Rate Zone Calculator
Calculate your 5 personalized training zones using the 220−age formula and Karvonen method. Get exact bpm ranges for fat burn, cardio, threshold, and peak zones.
- 5 training zones
- Karvonen formula
- Zone comparison chart
- Reference table
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Running Pace Calculator
Calculate your running pace in min/km and min/mile, or predict your finish time for any distance. Includes projected splits for 5K through marathon.
- Pace & finish time modes
- min/km & min/mile
- 5K–marathon splits
- Speed benchmarks
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VO2 Max Calculator
Estimate your VO2 max using Cooper test, Rockport walk test, or cycling test. See your fitness level rating compared to age and gender norms.
- 3 estimation methods
- Cooper 12-min run
- Rockport walk test
- Fitness level rating
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Steps to Calories Calculator
Convert your daily steps into calories burned. Shows distance walked, time estimate, and a comparison chart for 5K, 10K, 15K, and 20K step goals.
- Casual/brisk/fast pace
- Calories & distance
- 5K–20K comparison
- Weight-adjusted