Daily Figures Edition No Sign-Up • Free Forever Vol. XII — No. 204
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Fitness — Hydration

Water Intake Calculator

Enter your weight and exercise to estimate how much water to drink each day.

Filed by The Statistics Desk  |  Method: weight(lb) × 0.5 oz + exercise
Daily water
—
Recommended fluid intake.
Readout
Litres—
Cups (8 oz)—
Base (from weight)—
Exercise add-on—
Show our math
Enter your figures above to see the step-by-step working.
General guide — not medical adviceEverything computed client-side — nothing leaves this page

How the Water Intake Calculator Works

A widely used rule of thumb is to drink about half your body weight in ounces of water each day. This calculator applies that — multiplying your weight in pounds by 0.5 to get a baseline in fluid ounces — then adds roughly 12 ounces for every 30 minutes of exercise, since you lose fluid through sweat.

The result is shown in ounces, litres and cups. It is a general guide, not a medical prescription: hot weather, altitude, illness and pregnancy all raise your needs, and much of your water also comes from food.

ounces ≈ weightlb × 0.5 + exercise adjustment

Frequently Asked Questions

How much water should I drink a day?

A common guideline is about half your body weight in ounces — roughly 80 oz (2.4 L) for a 160 lb person — plus more when you exercise or it is hot. Individual needs vary.

Does exercise increase how much I need?

Yes. You lose water through sweat, so add roughly 12 ounces for every 30 minutes of activity. Hot or humid conditions raise it further.

Does other fluid and food count?

Yes — tea, coffee, milk and watery foods like fruit all contribute to your total fluid. The plain-water target is a guide, not the only source.

More From The Desk

Same plain method, different figures