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Free educational resource — not medical advice

Calculator

Water Intake Calculator

Estimate a general daily water target from your weight, exercise and climate.

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Water Intake Calculator

Enter your weight to estimate daily water.

This tool is for education and general interest only. It is not a medical device and must not be used to diagnose, treat or make health decisions. Always consult a qualified professional.

How to use it

  1. Step 1Enter your weight.
  2. Step 2Add daily exercise minutes and your climate.
  3. Step 3Read your general daily water estimate.

How much water do you need?

Water needs are personal. They rise with body size, exercise, heat and humidity, and fall in cool, restful conditions.

This tool blends a weight-based estimate with allowances for exercise and climate to give a general daily target.

Things to remember

Roughly a fifth of your water can come from food, especially fruit and vegetables. Drinks of all kinds also count toward the total.

For most healthy people, thirst is a reliable signal. Read our water guide, kidney guide, and hydration facts.

Questions & Answers

Frequently asked questions

Moderate coffee and tea still contribute to hydration overall, despite a mild diuretic effect.

No. It is a general educational estimate. Health, medication and pregnancy can change needs.

Pale-yellow urine and infrequent strong thirst are common everyday signs. Ask a professional about specific concerns.

Understand the science

Go beyond the numbers

Every tool pairs with a guide that explains the biology behind it in plain language.