Free Fitness Calculators

30+ science-based calculators for runners, cyclists, and triathletes. Calculate pace, heart rate zones, FTP, VO2 max, and more.

30+
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5M+
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Running Calculators

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Heart Rate Calculators

The gear these numbers assume

Every pace, zone and power figure on this page assumes something is measuring it. These are the three that cover running, cycling and the threshold work in between.

Garmin Forerunner 965 Garmin Forerunner 965

Multisport with the training-load and threshold metrics most of these calculations assume you can actually see day to day.

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COROS APEX 2 GPS Watch COROS APEX 2 Series GPS Watch

Sapphire titanium and the longest battery in its class, which is the deciding feature once sessions run past a few hours.

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Favero Assioma Uno Power Meter Pedal Favero Assioma Uno Power Meter Pedal

Single-sided pedal power, the cheapest honest way to start training with watts instead of estimating from heart rate.

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Cycling Calculators

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Performance & Fitness

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Interactive Tools & Timers

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