Water Intake Calculator
Daily drinking-water target from body weight, weekly exercise hours and a climate band, split into a drink schedule across your waking hours.
Fill in the values and calculate
The form sends itself back to this page — results print below, computed on the server.
No results yet: fill the form above and press Calculate.
About Water Intake Calculator
Body weight sets the baseline: 35 ml of water per kilogram per day is the working figure, so a 70 kg person drinks near two and a half litres before any adjustment.
Exercise hours and a climate band then move the number: heat asks for more, cold asks for less. The total is spread between your wake and bedtime so the plan becomes a list of times and sips instead of one overwhelming figure.
Questions about Water Intake Calculator
Why is the target tied to body weight?
Sweat and maintenance scale with mass, so the working figure is a per-kilogram amount rather than a fixed two litres.
Does exercise count if I only walk to work?
Not as activity. Only real training hours raise the target, about 700 ml per week-hour spread across the week.
Is the climate band enough?
It is a coarse stand-in for heat and dryness. Humid heat leans to the hot end; if unsure, use warm rather than hot.
Bookmark and homescreen
- Press Ctrl+B now (or Cmd+B on macOS) to bookmark this page in your browser.
- Drag this link to your bookmarks bar and it will always open this tool: Water Intake Calculator.
- On a phone: open in Chrome/Safari and use "Add to Home Screen" — the site ships a homescreen icon and manifest, so it installs like an app.
- Two addresses work:
https://useful-utilities.com/water-intake-calculator/andwater-intake-calculator.useful-utilities.com. Copy whichever you prefer.