๐ฆ Sweat Rate Calculator
Sweat loss (L) = (pre-exercise weight โ post-exercise weight) + fluid intake โ urine loss, divided by duration.
Enter your body weight before and after exercise, fluid intake and urine loss during exercise, and the exercise duration to calculate your hourly sweat rate, using the mass-balance formula used in sports science (ACSM).
How to use
- Enter your body weight before exercise (kg).
- Enter your body weight after exercise (kg).
- Enter the fluid you drank (L) and urine you produced (L) during exercise.
- Enter the exercise duration (hours).
- Your hourly sweat rate is calculated automatically.
FAQ
What's the formula?
Fluid loss from sweat (L) = (pre-exercise weight โ post-exercise weight) (kg, converted roughly 1kg โ 1L of water) + fluid intake (L) โ urine loss (L), then divided by exercise duration (hours) to get the hourly rate. This mass-balance approach is widely used in sports science.
What's a typical sweat rate?
It varies widely with exercise intensity, temperature, and body size, but a common range for general exercise is roughly 0.5-2 L per hour.
What's this useful for?
It helps you gauge how much fluid you need to replace during exercise โ especially useful for endurance sports or exercising in hot conditions, to help plan hydration and avoid dehydration.