---
title: "Water Intake Calculator — Daily Hydration by Weight & Activity"
description: "Calculate your daily water recommendation based on body weight, activity level, and climate. Compares US IOM, EFSA (Europe), Australian NHMRC, and WHO guidelines."
url: "https://worldcalculators.org/calculators/water-intake/"
canonical: "https://worldcalculators.org/calculators/water-intake/"
---

# Water Intake Calculator

Calculate your daily water recommendation based on body weight, activity level, and climate. Compares US IOM, EFSA (Europe), Australian NHMRC, and WHO guidelines.

## Quick answer

~33 mL/kg body weight is a widely-used baseline. For a 70 kg adult, that's about 2.3 L/day from beverages. US IOM: men 3.7 L total, women 2.7 L total (including ~20% from food). EFSA Europe: men 2.5 L, women 2.0 L. Australia: men 2.6 L, women 2.1 L. These differ partly due to methodology — the US value includes all water from all sources.

## Daily Water Recommendations by Country

The large US IOM figure includes all water — about 20% comes from food. Comparing only beverage recommendations, estimates are more similar (~2.0–2.5 L/day).

## Sources & Methodology

Daily fluid recommendations reference the U.S. National Academies (IOM) adequate intake and EFSA reference values, adjusted for body weight and activity.

Source: https://worldcalculators.org/calculators/water-intake/
Markdown mirror of the HTML page. Prefer this URL for RAG; the interactive calculator still lives on the HTML page.