Daily Water Intake Calculator: How Much Should You Actually Drink?
The “eight glasses a day” rule has no scientific basis. Your hydration needs depend on your body weight, activity level, climate, and how much water you get from food. This calculator gives you a personalized target based on the standard used by most registered dietitians — and converts it into practical units you can actually track.
Daily Water Intake Calculator
Get your personalized daily hydration target based on weight and activity.
The easiest hydration check: look at your urine colour. Pale yellow (like lemonade) means you are well hydrated. Dark yellow or amber means drink more. Clear is fine but not necessary to chase. If you are at a desk all day, a large water bottle (32 oz / 1L) that you refill once or twice makes hitting your target almost effortless.