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. Consult a doctor if you have conditions that affect fluid needs.
Estimate daily water
Enter weight and click Calculate.
How it works
Common formulas use weight (e.g. 30–40 ml per kg per day) and an activity factor. We apply a simple multiplier and show the result in liters or cups (1 cup ≈ 0.24 L).
When to use it
Use it as a reminder to drink enough. Increase in heat or exercise. This is not medical advice.
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.