Health & Fitness

Water Intake Calculator

Create a simple daily hydration planning estimate from body weight, a chosen ounces-per-pound factor and optional exercise fluid.

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Health & Body Metrics

Body composition, energy, strength and fitness estimates for general reference.

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How to use this water intake calculator

Enter the requested values above and select Calculate. Change any input to compare scenarios instantly.

Formula and method

Daily fluid estimate = body weight × chosen oz/lb factor + exercise minutes ÷ 30 × exercise fluid per 30 minutes.

Example

A 160 lb person using 0.5 oz/lb starts with 80 fl oz before any optional exercise adjustment.

What this calculator is useful for

Create a simple daily hydration planning estimate from body weight, a chosen ounces-per-pound factor and optional exercise fluid. Use it for quick estimates and comparisons; verify high-stakes health, training or measurement decisions with an appropriate authoritative source.

Frequently asked questions

What does the Water Intake Calculator calculate?

Create a simple daily hydration planning estimate from body weight, a chosen ounces-per-pound factor and optional exercise fluid.

How does the calculation work?

Daily fluid estimate = body weight × chosen oz/lb factor + exercise minutes ÷ 30 × exercise fluid per 30 minutes.

Is this calculator free?

Yes. ERICH Calculators is free to use and no account is required.

Source & assumptions

Reference and limitation

Hydration needs vary with climate, diet, health conditions, pregnancy, medications and exercise. This is a planning estimate, not medical guidance.

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Method, assumptions & corrections

See how formulas, sources and limitations are handled across ERICH Calculators.