Water Intake

A rough daily fluid estimate from body size.

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A common rule of thumb scales fluid with body weight and adds a bit for exercise. Kidneys, heat, and illness change need. This is an estimate.

How to use this tool

  1. Enter your measurements. Use the units shown on the labels. Do not send medical data anywhere.
  2. Read the estimate. These formulas are public rules of thumb, not a diagnosis.
  3. Talk to a clinician for decisions. Do not change medicine, diet, or training from this page alone.

Not a prescription

Over-drinking can be harmful. Some conditions require fluid limits. Ask a clinician if you have kidney, heart, or endocrine disease.

Frequently asked

Does coffee count?

Many people count most fluids. This page reports a water-equivalent estimate only.

Should I drink this during pregnancy?

Needs change. Use obstetric guidance, not this estimate.

Is 8 glasses required?

No. That slogan is not individualized.

Should I force this volume if I have kidney disease?

No. Fluid limits need a clinician. This target is only an estimate.

Can I switch liters and ounces?

Yes.