Free browser-based tool
Water Intake Calculator
Calculate your daily water intake based on body weight, activity level, and climate conditions.
Your Daily Water Goal
(3,245 ml)
13
Glasses of water
(250 ml / glass)
3
Per 6-hour block
(spread throughout day)
💡 Tip: Drink a glass first thing in the morning and one with every meal. Your urine should be pale straw yellow — that's the best real-time hydration indicator.
How Water Intake is Calculated
Your daily water needs depend on several factors. This calculator uses a formula that considers:
1. Base Calculation
Standard recommendation: 30-35 ml per kg of body weight
2. Activity Adjustment
Add 12 oz (350 ml) for every 30 minutes of exercise
3. Climate Factor
Hot or humid weather increases water loss through sweat—add 500-1000 ml
Benefits of Proper Hydration
Brain Function
Improves concentration, memory, and cognitive performance
Physical Performance
Enhances endurance and reduces fatigue during exercise
Heart Health
Maintains blood volume and supports cardiovascular function
Temperature Control
Regulates body temperature through perspiration
Kidney Function
Helps kidneys filter waste and prevent stones
Skin Health
Keeps skin hydrated and may improve appearance
Signs of Dehydration
Dark yellow urine
Should be pale yellow or clear
Dry mouth and lips
Saliva production decreases
Fatigue and dizziness
Low blood volume affects energy
Headache
Brain tissue loses water