Hydration Calculator
Estimate daily fluid intake from body weight and daily training time so you can hydrate consistently.
How hydration is estimated
The base estimate is body weight in kilograms × 0.033 liters, with extra fluids estimated from workout duration and intensity.
Daily fluid needs vary with climate, sodium losses, caffeine, and illness. Increase intake during heat, high sweat, or illness.
Method and source:Body-water and exercise hydration guidelines
Last reviewed: July 2026
How to use this calculator
Use the calculator as a practical starting point, then apply the result in the context of your training, recovery, and individual response.
- 1Enter the requested measurements or performance data.
- 2Choose the units and options that match your situation.
- 3Calculate, review the method and limitations, and adjust sensibly.
Frequently asked questions
How does this calculator work?
The base estimate is body weight in kilograms × 0.033 liters, with extra fluids estimated from workout duration and intensity.
How accurate is this calculator?
Daily fluid needs vary with climate, sodium losses, caffeine, and illness. Increase intake during heat, high sweat, or illness.
Using your results
Every calculated 1RM is an estimate. Use the range as a training guide, and choose working weights that match your experience, technique, and current condition.
Safety tips
- Warm up thoroughly before attempting heavy lifts.
- Use controlled movement and proper technique.
- Use a spotter or safety equipment for near-maximal lifts.
- Increase the load gradually to reduce injury risk.
- Stop if you feel pain and allow enough time for recovery.
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