How is the fluid range calculated?

This illustration multiplies adult body weight by 30-35 mL per kilogram per day. It is a rough planning rule, not a universal hydration requirement.

Should I drink this much plain water in addition to food and drinks?

No. Do not interpret the range as extra plain water to consume. Food and beverages also contribute to hydration, and individual needs differ.

What if I have a fluid restriction or exercise in heat?

Follow a clinician's fluid restriction for relevant medical conditions. Heat, activity, pregnancy, and illness can alter needs beyond this simplified illustration.

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Water Intake Calculator

Explore a rough adult fluid-planning range based on body weight. This is not a prescribed amount of plain water to drink.

Guide

Interactive workspace

No account required

The estimate runs locally; no health-data upload is required. Optional analytics and advertising have separate consent and privacy disclosures. Avoid sensitive personal inputs.

Adult weight (kg)

Rough adult fluid-planning illustration: 30-35 mL/kg/day, not a prescribed amount of plain water to drink. Food and other beverages also contribute. Heat, exercise, pregnancy, and health conditions change needs. Follow clinician-set fluid restrictions for kidney, heart, or other conditions.

Illustrative daily fluid range: 2.1-2.45 L/day
Same range in millilitres: 2,100-2,450 mL/day

How to use it

Enter adult body weight in kilograms.
Review the illustrative range in litres and millilitres.
Consider food, other drinks, climate, activity, and any clinician-set fluid restrictions.

What is Water Intake Calculator?

Explore a rough weight-based adult daily fluid range with explicit health and hydration limitations.

How it works

Multiply adult body weight in kilograms by 30 and 35 mL to illustrate a daily fluid range. Show the same range in millilitres and litres without applying exercise or climate adjustments.

Common uses

Understand a simple weight-based fluid calculation.
Compare litres and millilitres for the same illustrative range.
Prepare hydration questions for a healthcare professional.

Limitations

Results depend on the browser, network, input, and external service involved.
This tool is informational and does not replace specialist diagnostics or professional advice.

Frequently asked questions

How is the fluid range calculated?: This illustration multiplies adult body weight by 30-35 mL per kilogram per day. It is a rough planning rule, not a universal hydration requirement.
Should I drink this much plain water in addition to food and drinks?: No. Do not interpret the range as extra plain water to consume. Food and beverages also contribute to hydration, and individual needs differ.
What if I have a fluid restriction or exercise in heat?: Follow a clinician's fluid restriction for relevant medical conditions. Heat, activity, pregnancy, and illness can alter needs beyond this simplified illustration.

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