Running
Sweat Rate Calculator
Estimate hourly sweat loss from pre- and post-exercise bodyweight and fluid intake.
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Sweat loss is estimated from bodyweight change plus fluid consumed, minus urine produced, over exercise time.
Method and limitations
Sweat loss is estimated from bodyweight change plus fluid consumed, minus urine produced, over exercise time. The exact method can differ between organisations, sports and populations, so use this page as a transparent starting point rather than a final decision.
For current standards, check the official governing body or competition notice. Keep a record of your inputs so you can compare changes over time under consistent conditions.
Frequently Asked Questions
Disclaimer: This calculator is for general education and fitness planning only. It does not provide medical advice or guarantee eligibility. Read the full disclaimer.