Sweat Rate Calculator
Litres per hour from pre/post-exercise weights — the only personal number that makes hydration plans real.
Sweat rates span 0.5 to 2.5+ L/h between individuals and conditions — which is why generic 'drink X' advice fails athletes. Test in race-like heat and intensity, then plan to replace 60–80% of losses in-session (full replacement causes sloshing). A 2% bodyweight loss measurably degrades performance; that's the line the plan defends.
Formula
For general information only — not medical or training advice. Estimates vary between individuals; consult a qualified professional before changing your exercise or nutrition routine.
Litres per hour from pre/post-exercise weights — the only personal number that makes hydration plans real. The Sweat Rate Calculator is a free, private sweat rate tool — every result computes instantly in your browser with no sign-up and no data upload.
About Sweat Rate Calculator
Sweat rates span 0.5 to 2.5+ L/h between individuals and conditions — which is why generic 'drink X' advice fails athletes. It applies sweat = (pre − post weight) + fluid drunk; rate = sweat ÷ hours. Use the Sweat Rate Calculator to get an instant, clearly-explained result with the working shown step by step — free, private and with the source method cited.
How to use Sweat Rate Calculator
- 1Enter your details in the Sweat Rate Calculator input fields above.
- 2The result updates instantly with the working and reference bands shown.
- 3Adjust any value to explore how it changes the outcome — it's free and unlimited.
Why use Sweat Rate Calculator?
- ✓Instant sweat rate result that recomputes as you type — no waiting, no page reloads
- ✓100% client-side: your health data never leaves your browser
- ✓Shows the actual formula and your numbers substituted in, so you can see exactly how the result is reached
- ✓Based on published, citable sources (ACSM Position Stand — exercise and fluid replacement, 2007)
- ✓Free forever with no sign-up, account or app install
Frequently asked questions
How does the Sweat Rate Calculator work?+
Sweat rates span 0.5 to 2.5+ L/h between individuals and conditions — which is why generic 'drink X' advice fails athletes. The calculation uses the formula: sweat = (pre − post weight) + fluid drunk; rate = sweat ÷ hours. Everything runs instantly in your browser as you type — your inputs are never uploaded.
Is the Sweat Rate Calculator accurate, and what is it based on?+
The method is traceable to authoritative sources: ACSM Position Stand — exercise and fluid replacement, 2007. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.
Is the Sweat Rate Calculator free and private?+
Yes. It's completely free with no sign-up, and all computation happens locally in your browser, so none of your health data ever leaves your device.
Can I use this for medical decisions?+
This tool is for general fitness information only, not medical or training advice. Consult a professional before changing your routine.
What can I use the Sweat Rate Calculator for?+
It's commonly used for sweat rate, sweat rate test, fluid loss exercise. Litres per hour from pre/post-exercise weights — the only personal number that makes hydration plans real.
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