Free calculators built around the science. Enter your numbers, get precise zones and targets.
2 tools
Enter your age and resting heart rate. Get your exact Zone 2 range and all five training zones using the Karvonen formula. Know precisely where every run should land.
Use toolFill in any one value and all others update instantly. Convert between min/km, min/mile, and km/h. See projected finish times for 5K, 10K, half marathon, marathon, and 400m lap.
Use toolMy Plan
The calculators give you the numbers. A personalised coaching block tells you exactly what to do with them, week by week.
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