Result
Daily water target
3.13 L
- In litres3.13 L
- In US fl oz106 oz
- In 8 oz cups~13.2 cups
- In 500 mL bottles~6.3 bottles
- Per hour while awake (16 hr)195 mL
How to use this calculator
- Enter your bodyweight.
- Add average exercise minutes per day.
- Pick your typical climate.
- Sip throughout the day — don't try to chug it all at once.
About this tool
The "8 glasses a day" rule is a rough starting point, not a precise prescription. A better baseline: 35 mL per kg of bodyweight (about 0.5 oz per pound). Add ~500 mL for every 30 minutes of exercise. Hot and humid climates increase needs by 20–35%. This includes water from all sources — coffee, tea, soft drinks, and food contribute. Listen to your body: pale-yellow urine usually means well-hydrated; dark yellow means drink more. Overdrinking water is rare but possible (hyponatremia), most often during long endurance events without electrolyte replacement.
Frequently asked
Yes. The old "diuretic, cancels out" myth is false — caffeinated drinks net you about 80% of their water content as hydration. Plain water is still ideal but tea and coffee count.
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