Water Intake Calculator

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Water Intake Calculator

Recommended daily water intake from weight, activity, and climate

Gender
Climate
Wake / sleep hours (optional)
Recommended daily intake —
— L
— fl oz
— cups
IoM cross-check (drinks only) —

How we calculated

Base (weight × coefficient) —
Activity adjustment —
Climate adjustment —

Suggested hourly pacing

Fill wake/sleep hours to see hourly pacing

How we calculate

The base amount uses a body-weight coefficient (35 ml/kg for males, 31 ml/kg for females, 33 ml/kg as a neutral default), then adds activity and climate adjustments (moderate activity +700 ml, hot climate +500 ml, etc). The result is cross-checked against the U.S. Institute of Medicine recommendation within a ±20% range. Sustained intake above 5 L/day increases hyponatremia risk — consult a doctor if you regularly exceed that.

See also: Sleep Cycle Calculator (wellness pair), Unit Converter (ml ↔ fl-oz), Cron Expression Generator (hydration reminders).

Water Intake Calculator

Calculate your recommended daily water intake from weight, activity, and climate. 4 unit conversions + IoM cross-check + safety threshold, all local.

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