Wellness estimates

Water Intake Calculator

Estimate daily water needs based on body weight, activity, and climate. Use this Health estimates tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
Quick intro
Calculator
Result
Explanation
Common questions
Related tools

Calculator tool

How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

The estimate starts with milliliters per kilogram of body weight, adds fluid for active minutes, and then applies a climate adjustment. It is a hydration planning estimate, not a medical fluid prescription.

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

Does coffee count as water?

Coffee, tea, milk, and many foods contribute fluid, but caffeine and alcohol can change hydration needs. Use the result as a daily fluid target, not only plain water.

Should athletes drink more?

Yes. Activity and sweat loss can increase the estimate.