Water Intake Calculator
A simple way to set a hydration target: scale it to your body weight, then add a little for exercise. This shows the number in liters, ounces, cups and glasses so you can track it however you like.
Your numbers
Result
- In fluid ouncesUS fl oz
- 91
- In glasses (250 ml)
- 10.8
| Unit | Amount |
|---|---|
| Liters | 2.70 |
| Fluid ounces (US) | 91 |
| Cups (8 fl oz) | 11.4 |
| Glasses (250 ml) | 10.8 |
How the target is worked out
A common guideline is about 35 ml of water per kilogram of body weight — roughly half your body weight in ounces. A 70 kg person lands near 2.45 liters (about 83 fl oz). Then add roughly 250 ml (8 oz) for every 30 minutes of exercise to replace what you sweat out.
It is a starting point, not a rule
The old "8 glasses a day" is a rule of thumb, not a law — real needs vary with heat, humidity, altitude, illness and diet. Food (especially fruit and vegetables) and other drinks count toward your total too. The most reliable signal is your body: pale-yellow urine usually means you are well hydrated.
Can you drink too much?
Rarely, but yes. Drinking extreme amounts in a short time can dilute blood sodium (hyponatremia), which is dangerous. Spread intake through the day rather than forcing large volumes at once, and let thirst guide you alongside the target.
Informational and educational result. Not a substitute for professional advice.
Frequently asked questions
Sources
- U.S. National Academies — dietary reference intakes for water
- Common hydration guideline (~35 ml/kg body weight)
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Copy the code and paste it into your site or blog. Credit with a link back to Contania is included, and the height adjusts itself.
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