Water Intake Calculator

Get a rough daily water intake (in cups or liters) based on body weight and activity level. Guidelines vary; this is for general reference only.

Water Intake Calculator

How it works

Common formulas use weight (e.g. 30–35 ml per kg) and an activity factor. We apply a simple multiplier and show the result in your preferred unit.

When to use it

Use it as a reminder to drink enough. Increase in heat or exercise. Consult a doctor if you have conditions that affect fluid needs.

Frequently asked questions

Does this include food moisture?

Many guidelines count all fluids. We show total recommended intake; food contributes to that.

What about athletes?

We include an activity factor. For heavy training you may need more; adjust by thirst and urine color.