Health · Hydration & Fluid Balance

Sweat Loss Rate Calculator

Estimate session sweat loss and rate while keeping body-mass change, intake, urine, and time visible.

Health · Hydration & Fluid Balance

Enter your measurements

Private in-browser calculation · no account or saved health record
The derived sweat-rate result must be 0 to 6 L/hour in this release; that cap is not a target.

Health values stay in this browser tab. They are not added to the URL, analytics, storage, or a cloud record.

Health result

Enter valid values to see the result.

Your entries are calculated in this browser and are not submitted to 365CALCS.COM.

Quick guide

How to use this calculator

  1. Use the labels and unit notes to enter the requested measurement, date, time, or observation exactly as recorded.
  2. Check the visible method, population, and unit basis before using the result; switch modes rather than converting values mentally.
  3. Read the calculation audit and limitations together. The result supports measurement or tracking and does not replace diagnosis, treatment, or urgent medical assessment.

Calculation method

How the sweat loss rate calculator works

Sweat loss (L) = pre mass - post mass (kg) + intake (L) - urine (L); sweat rate = loss / hours.

The result is a session estimate for comparison in similar conditions, not a fixed personal constant.

Worked example

Sweat Loss Rate example

70 kg before, 69 kg after, 0.5 L intake, no urine, and two hours imply 1.5 L or 0.75 L/hour.

Sweat loss (L) = pre mass - post mass (kg) + intake (L) - urine (L); sweat rate = loss / hours.

Supported inputs

Precision and limits

Supported purpose

Wet clothing, scale error, food, incomplete drink or urine measurements, and other losses can distort the estimate. It does not prescribe replacement.

Measurement quality

The output is only as reliable as the entered measurement, device, timing, units, and applicable reference population. Recheck unexpected values against the original record.

Clinical boundary

This calculator does not diagnose a condition, choose treatment, change medication, or determine that an urgent symptom is safe to monitor at home. Contact an appropriate health professional or local emergency service when the situation may be urgent.

Privacy

Entered health values and results stay in this browser tab. They are not placed in URLs, analytics, logs, local storage, session replay, or a cloud record by this calculator.

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