yCalculator

Water Intake Calculator

Last updated: April 2026

Unit system

kg

Activity level

Daily water intake

2.5 litres/day

2,450 ml / 83 fl oz per day

Breakdown

Weight used70 kg
Base need2,450 ml
Activity adjustment0 ml

Hydration note

This estimate is a practical starting point. Heat, sweating, pregnancy, breastfeeding, illness, caffeine, alcohol, and salty meals can all change daily fluid needs.

Related calculators:

  • TDEE Calculator
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  • Calories Burned Calculator

What is a water intake calculator?

A water intake calculator estimates how much fluid you may need each day based on your body weight and activity level.

How daily water intake is calculated

This calculator uses 35ml per kilogram of body weight as the base amount, then adds extra water for moderate or high activity.

When to use this calculator

Use it when setting a daily hydration goal for training, general health tracking, or building a routine around meals and workouts.

Limitations

Hydration needs vary widely. This tool is not medical advice, and people with kidney, heart, or fluid-balance conditions should follow clinical guidance.

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.

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