How is my water intake calculated?

I use a formula based on WHO and scientific guidelines: approximately 35ml per kilogram for men and 31ml for women as a base, plus 12ml for each minute of daily exercise, adjusted by a climate factor (0.9x for cold, 1.0x for moderate, 1.2x for hot environments).

Does coffee, tea, or juice count toward my water intake?

Yes, all beverages contribute to hydration. However, water is the most efficient source. Caffeinated beverages have a mild diuretic effect, so count them as roughly 50–75% of their volume toward your goal.

Should I drink more water if I'm pregnant or breastfeeding?

Yes, pregnant women should add about 300ml/day to their baseline, and breastfeeding mothers should add about 700ml/day. Always consult your healthcare provider for personalised advice.

What are the first signs of dehydration?

Common early signs include feeling thirsty, having a dry mouth, dark yellow and strong-smelling urine, feeling tired or dizzy, and experiencing headaches.

How to build a habit of drinking water?

Keep a water bottle near you throughout the day. Drink a glass immediately after waking up, set reminders on your phone, and drink a glass with every meal.

Can I drink too much water?

Yes. Drinking extreme amounts of water in a short time can lead to hyponatremia (water intoxication), which dilutes sodium in your blood. Stick to your calculated goal and space it out throughout the day.

Does sweating from exercise change my goal?

Absolutely. For every hour of intense exercise, you can lose 0.5 to 2 liters of sweat. The calculator automatically adds extra water based on your daily exercise minutes.

Is sparkling water as hydrating as still water?

Yes. Carbonated water is just as effective for hydration as still water. However, some people might feel fuller faster due to the bubbles, which could lead to drinking less overall. Choose whichever you prefer!

Do fruits and vegetables really count towards hydration?

Yes! About 20% of your daily water intake comes from food. Cucumber, watermelon, and spinach are over 90% water. My calculator takes this into account in the general recommendation.

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Knowledge Base

Dive deeper into the science of hydration.

Articles

The Role of Electrolytes

Water alone is sometimes not enough. Learn why sodium, potassium, and magnesium are critical for proper cell hydration.

When you sweat, you don't just lose water—you also lose vital minerals called electrolytes. Sodium, potassium, and magnesium help balance the amount of water in your body and pH levels, whilst moving nutrients into your cells. If you drink large amounts of pure water without replenishing electrolytes during heavy exercise, you risk muscle cramps and fatigue. Consider adding a pinch of salt or drinking electrolyte water after intense workouts.

Hydration and Brain Performance

Even mild dehydration (1-3%) can impair brain function, memory, and mood. Keep your cognitive performance at its peak.

Your brain is roughly 73% water. Studies show that merely a 2% drop in brain hydration can cause short-term memory loss, trouble with basic math, and difficulty focusing. It also significantly affects your mood—making you feel more anxious, tired, or irritable. By keeping your hydration consistent throughout the whole day (rather than chugging at night), you ensure a steady flow of nutrients and oxygen to your brain.

How to Tell If You Are Hydrated

Thirst is usually a late indicator of dehydration. Learn the early signs to watch out for.

The most reliable daily check is looking at your urine color: it should be pale or light yellow (like lemonade). If it is dark yellow or amber, you need to drink water immediately. Other signs of chronic dehydration include persistent dry skin, chapped lips, fewer trips to the bathroom, and unexplained fatigue mid-afternoon. Don't wait for extreme thirst to start drinking!

Building the Habit: Micro-steps

Motivation gets you started, but habits keep you going. Learn how to stick to your goal.

The secret to consistent hydration is not willpower, but environment design. Place a water bottle in every room where you spend more than 2 hours. Drink a small glass of water immediately after every bathroom break. These "habit stacking" techniques anchor your drinking to existing cues in your day, making it an effortless part of your lifestyle.

Scientific Basis

My calculator is built upon guidelines from global health institutions, ensuring safe and tailored results.

Knowledge Base

Articles

The Role of Electrolytes

Hydration and Brain Performance

How to Tell If You Are Hydrated

Building the Habit: Micro-steps

Scientific Basis

U.S. National Academies of Sciences

World Health Organization (WHO)

EFSA Guidelines (Europe)

NHS (United Kingdom)

Role of Hydration (Mayo Clinic)

Frequently Asked Questions