Health & Fitness
Water Intake Calculator
Recommended daily water intake based on weight and activity.
How this water intake calculator works
This free online water intake calculator takes the numbers you enter and applies a standard formula for this kind of calculation, showing the result instantly with no page reload. Recommended daily water intake based on weight and activity.
Everything runs client-side in JavaScript, so your inputs never leave your device — there's no server, no account and no tracking involved in getting your answer.
Frequently asked questions
No — it's a baseline estimate from body weight and exercise alone. Hot weather, high-sodium diets, and illness all increase fluid needs beyond this estimate.