How much water should you drink per day?

The "eight glasses a day" rule is a convenient shortcut, not a medical prescription. Your actual needs depend on body weight, climate, activity level, and what you eat. Most adults fall somewhere between 1.5 and 3 liters of total fluid per day, with food accounting for roughly 20% of that.

A practical starting point: 35 ml per kilogram of body weight. A 70 kg adult lands at around 2.4 liters; a 90 kg adult at roughly 3.1 liters. These are estimates — urine color and how you feel on a given day are still your best real-time signals.

Factors that raise your needs:

• Physical exercise (add at least 500 ml for moderate workouts)
• Hot or humid weather
• Fever, vomiting, or diarrhea
• Pregnancy or breastfeeding

A note on beverages: Water, herbal teas, and diluted juices all count. Coffee and alcohol have a mild diuretic effect but still contribute net fluid in normal amounts.

The hard part isn't knowing the number — it's actually drinking consistently. Setting a daily goal and tracking cup by cup tends to work better than trying to gulp large amounts at once.

Gota lets you set your own daily goal and log each cup with a single tap. Your progress ring fills as you go — no account, no internet, nothing leaves your phone. Download free on Google Play.