🏃 Health & Fitness
Water Intake Calculator
A common guideline is about 35 millilitres of water per kilogram of body weight, plus extra for exercise and hot weather. Needs rise with activity, heat and altitude, and food typically supplies a further fifth of daily water.
How it works
Body weight
Exercise per day
Climate
Water per day
Glasses (250 ml)
Millilitres per kg
Frequently asked questions
How do I use the Water Intake Calculator?
Fill in the fields above — the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.