Hydration Calculator
Calculate your daily water intake needs based on your weight, activity level, and climate.
More active = more water needed
Hot climates increase water needs
Enter your details and click calculate to see your results
Why Hydration Matters
Water is essential for nearly every bodily function, from regulating body temperature to transporting nutrients and removing waste. Proper hydration improves energy, cognitive function, physical performance, and overall health.
How Much Water Do You Need?
Individual water needs vary based on several factors:
- Body weight: Larger bodies need more water
- Activity level: Exercise increases water loss through sweat
- Climate: Heat and humidity increase sweat loss
- Health status: Illness, pregnancy, and nursing increase needs
- Diet: High-protein or high-sodium diets require more water
Our Calculation Method
We use a body-weight-based formula recommended by nutrition experts:
Base Water = Body Weight (kg) × 33ml per kg
Then adjusted for activity level, climate, and special conditions
Signs of Good Hydration
Well Hydrated
- • Pale yellow urine
- • Urinating every 2-4 hours
- • Good energy levels
- • Moist lips and mouth
Dehydrated
- • Dark yellow/amber urine
- • Dry mouth and lips
- • Headache or fatigue
- • Dizziness or confusion
What Counts as Water?
While plain water is best, other fluids and foods contribute to hydration:
- 100% hydrating: Water, sparkling water, herbal tea
- ~90% hydrating: Regular tea, coffee (moderate amounts)
- Water-rich foods: Watermelon, cucumber, oranges, lettuce (85-95% water)
- Limited benefit: Sugary drinks, alcohol (actually increase water needs)
Special Considerations
During Exercise
Add 400-800ml (12-24 oz) of water for every hour of moderate exercise. For intense exercise or hot conditions, increase further and consider electrolyte replacement.
Pregnancy & Nursing
Pregnant women need an extra 300ml per day, while breastfeeding mothers need an additional 700ml to support milk production and prevent dehydration.
Hot Weather
In hot or humid conditions, you may need 20-30% more water than usual due to increased sweating. Monitor urine color and increase intake as needed.
Frequently Asked Questions
Can you drink too much water?
Yes, though it's rare. Overhydration (hyponatremia) can occur if you drink excessive amounts very quickly, diluting blood sodium levels. Stick to recommended amounts and spread intake throughout the day.
Does coffee dehydrate you?
No. While caffeine has a mild diuretic effect, the water in coffee more than compensates. Regular coffee drinkers develop tolerance to caffeine's diuretic effects.
What if I don't like plain water?
Try infusing water with fruit, herbs, or cucumber. Herbal teas, sparkling water, and water-rich foods like soups and fruits are excellent alternatives.
Should I drink 8 glasses a day?
The "8×8 rule" (eight 8-oz glasses) is a good general guideline but doesn't account for individual needs. Use our calculator for a personalized recommendation based on your specific factors.