Sweat Rate Calculator
Calculate sweat rate from pre/post bodyweight and fluid intake, with sodium loss estimate and hydration protocol.
Inputs
Fill in the inputs and press Calculate to see your science-backed results.
How to use Sweat Rate Calculator
Calculate sweat rate from pre/post bodyweight and fluid intake, with sodium loss estimate and hydration protocol.
Choose measurements that describe your actual session or situation, confirm the units, then calculate. Read the result alongside its assumptions and use the tool again when your inputs change.
Inputs explained
Pre-exercise weight (kg)
Enter a measured or estimated value (minimum 30) (maximum 200), using the unit indicated in the field label.
Post-exercise weight (kg)
Enter a measured or estimated value (minimum 30) (maximum 200), using the unit indicated in the field label.
Fluid intake during (ml)
Enter a measured or estimated value (minimum 0) (maximum 3000), using the unit indicated in the field label.
Duration (min)
Enter a measured or estimated value (minimum 15) (maximum 300), using the unit indicated in the field label.
Temperature (°C)
Enter a measured or estimated value (minimum 5) (maximum 40), using the unit indicated in the field label.
Sweat sodium (mg/L, optional)
Enter a measured or estimated value (minimum 200) (maximum 2500), using the unit indicated in the field label.
How to interpret the output
Keep testing conditions and intensity consistent. Estimates from field tests do not replace laboratory assessment.
Repeat measurements using similar conditions when monitoring trends. Numerical predictions can vary with input accuracy, measurement method and individual circumstances.
Limitations and responsible use
Sweat rate varies by environment, fitness, and acclimatization. Measure under your typical training conditions.
Read the full disclaimerFrequently asked questions
What does the Sweat Rate Calculator estimate?
Calculate sweat rate from pre/post bodyweight and fluid intake, with sodium loss estimate and hydration protocol.
Which information do I need for this cardio tool?
Provide Pre-exercise weight (kg), Post-exercise weight (kg), Fluid intake during (ml), Duration (min), Temperature (°C), and any additional fields shown above. Use your own relevant measurements and the units indicated in each field.
How should I interpret the result?
Keep testing conditions and intensity consistent. Estimates from field tests do not replace laboratory assessment. Compare results with your goals and other relevant observations rather than using a single output to make a major decision.
Disclaimer: Sweat rate varies by environment, fitness, and acclimatization. Measure under your typical training conditions. Read the medical disclaimer.
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