Daily Water Intake Calculator

Find your recommended daily water intake based on body weight and activity level.

Hot weather, pregnancy or illness can raise your needs — adjust to suit.

Aim for around

Tell us your weight and activity level and we'll suggest a daily target.

How it works

We use a baseline of about 35 ml of water per kilogram of body weight, then add 350–700 ml for moderate-to-high activity to replace fluid lost through sweat.

This is a general guideline. Hot climates, pregnancy, illness, and certain medications can change your needs — listen to your body and check with a clinician if unsure.

Frequently asked