Health

Water Intake Calculator

Units:
kg
yrs
Daily water intake
2,850ml
4L2.5L1L
2,850 ml
96.4 fl oz
9.1 glasses

How to get there

🥗
570 ml
From food (~20%)
💧
2,280 ml
From drinking (9.1 glasses)
Food 20%Drinking 80%

When to drink today

🌅
Morning (wake up)
2 glasses
Rehydrate after sleep — your body loses water overnight.
🍽️
Before each meal
1 glass
Drinking before meals aids digestion and helps control appetite.
🏃
During exercise
150–250ml every 20 min
Drink regularly during physical activity, especially in the heat.
☀️
Afternoon (2–4 PM)
1–2 glasses
Combat the afternoon energy slump with a glass of water.
🌙
Evening (before bed)
1 glass
Prepare for overnight hydration but avoid too much to prevent disruption.
Note: These recommendations are based on general health guidelines. Individual needs vary based on health conditions, medications, and specific circumstances. Consult a healthcare professional for personalized advice.

Understanding Daily Water Intake

Proper hydration is essential for maintaining optimal health. Water plays a crucial role in nearly every bodily function, from regulating body temperature to transporting nutrients and removing waste. Our water intake calculator helps you determine how much water you should drink daily based on your individual factors.

Why Hydration Matters

The human body is approximately 60% water. Staying properly hydrated helps:

  • Regulate body temperature through sweating
  • Transport nutrients and oxygen to cells
  • Flush out toxins and waste products
  • Lubricate joints and protect organs
  • Support cognitive function and mood
  • Maintain healthy skin and digestion

How We Calculate Your Water Needs

Our calculator uses the widely-accepted formula of approximately 33ml of water per kilogram of body weight as a baseline. This is then adjusted based on:

Factor Adjustment Reason
Activity Level +10-40% Exercise increases fluid loss through sweat
Hot Climate +5-10ml/kg Higher temperatures increase perspiration
Pregnancy +300ml Supports increased blood volume and amniotic fluid
Breastfeeding +700ml Replaces fluids lost through milk production

Signs of Dehydration

Watch for these common signs that you may not be drinking enough water:

  • Dark yellow urine - Well-hydrated urine should be pale yellow
  • Thirst - By the time you feel thirsty, you may already be mildly dehydrated
  • Fatigue - Even mild dehydration can cause tiredness
  • Headaches - Dehydration is a common headache trigger
  • Dry mouth and skin - Lack of moisture affects tissues
  • Dizziness - Can occur with more significant dehydration

Tips for Staying Hydrated

  • Start your day with a glass of water
  • Carry a reusable water bottle
  • Set reminders to drink throughout the day
  • Drink water before, during, and after exercise
  • Eat water-rich foods like fruits and vegetables
  • Drink a glass of water with each meal

Frequently Asked Questions

How much water should I drink a day?

The general recommendation is about 2-3 liters (8-12 cups) per day for adults, but this varies based on body weight, activity level, climate, and health conditions. Use our calculator to get a personalized recommendation based on your specific factors.

Can I drink too much water?

Yes, it's possible to drink too much water, a condition called hyponatremia or water intoxication. This occurs when you drink so much water that it dilutes the sodium in your blood. However, this is rare and typically only occurs with extreme water consumption (several liters in a short period). For most people, following our calculated recommendation is safe.

Do coffee and tea count toward my water intake?

Yes, coffee and tea do contribute to your daily fluid intake. While caffeine has a mild diuretic effect, the water content in these beverages still provides net hydration. However, water remains the best choice for hydration as it has no calories or additives.

Should I drink more water when exercising?

Absolutely. During exercise, you lose water through sweat. It's recommended to drink about 500ml (17oz) of water 2-3 hours before exercise, 250ml (8oz) every 15-20 minutes during exercise, and continue hydrating after your workout. For intense exercise lasting over an hour, consider drinks with electrolytes.

How do I know if I'm drinking enough water?

The easiest way to check your hydration status is by observing your urine color. Pale yellow (like lemonade) indicates good hydration, while dark yellow or amber suggests you need more fluids. Also pay attention to how often you urinate - going every 2-4 hours during waking hours is typical for good hydration.

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Aggiornato Febbraio 2026 · Testati e verificati

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