Personal, Not One-Size-Fits-All

How this water calculator works

A simple estimate built from the details that change hydration needs most.

Body Size

Weight and height set a sensible baseline for everyday fluid needs.

Activity

Exercise increases the water lost through breathing and sweat.

Climate

Warm, humid days raise needs before you notice thirst.
Hydration Basics

Why ‘8 glasses a day’ doesn’t fit everyone

Eight glasses is memorable, not universal. A smaller person at a desk on a cool day may need less than someone training outdoors. Fruit, vegetables, soups and yogurt also supply water.

Use your result as a starting point. Sip steadily, notice thirst and urine colour, then adjust for exercise, heat, illness and clinical advice. Consistency matters more than a perfect number.Make it Automatic

Make it Automatic

5 easy ways to hit your daily goal

Small cues beat willpower. Build water into moments that already happen.

01

Set reminders

Tie prompts to your routine so water is easy to remember.
02

Keep water visible

Place a bottle where you work and relax.
03

Pair sips with habits

Drink after waking, with meals and after calls.
04

Prepare for exercise

Sip before, during and after longer sessions.
05

Use a bottle you like

A useful volume makes progress easier to see.
It All Adds Up

Do coffee, tea and other drinks count?

Yes. Water is a great default, but coffee, tea, milk, juice and water-rich foods contribute fluid. Normal caffeinated servings still add more fluid than they remove. Keep sugary drinks occasional.

Water

Juice

Coffee

Tea

Soda

Alcohol

Got Questions?

Water intake calculator FAQs

Practical guidance for building a hydration habit that works in real life.

Your needs depend on body size, activity, climate, food and health. This calculator gives a useful starting point, then your thirst and routine help you fine-tune it.

Your needs depend on body size, activity, climate, food and health. This calculator gives a useful starting point, then your thirst and routine help you fine-tune it.

Your needs depend on body size, activity, climate, food and health. This calculator gives a useful starting point, then your thirst and routine help you fine-tune it.

Your needs depend on body size, activity, climate, food and health. This calculator gives a useful starting point, then your thirst and routine help you fine-tune it.

Your needs depend on body size, activity, climate, food and health. This calculator gives a useful starting point, then your thirst and routine help you fine-tune it.

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