Human Calculators
Daily water intake calculators for adults — men, women, elderly, weight-based, and weather-based.
Most popular in Human Calculators
Adult Daily Water Intake
Personalized daily water target for healthy adults, adjusted for weight, activity, and climate.
Open calculatorElderly Water Intake (65+)
Daily hydration target for older adults, with a safe minimum floor and climate adjustments.
Open calculatorWater Intake for Weight Loss
Higher-end daily target with pre-meal water boost that supports satiety and weight loss.
Open calculatorExplore the full library
Water Intake — Alabama
Daily water target for alabama residents — local climate factored in.
OpenWater Intake — Alaska
Daily water target for alaska residents — local climate factored in.
OpenWater Intake — Arizona
Daily water target for arizona residents — local climate factored in.
OpenWater Intake — Arkansas
Daily water target for arkansas residents — local climate factored in.
OpenWater Intake — California
Daily water target for california residents — local climate factored in.
OpenWater Intake — Colorado
Daily water target for colorado residents — local climate factored in.
OpenWater Intake — Connecticut
Daily water target for connecticut residents — local climate factored in.
OpenWater Intake — Delaware
Daily water target for delaware residents — local climate factored in.
OpenWater Intake — Florida
Daily water target for florida residents — local climate factored in.
OpenWater Intake — Georgia
Daily water target for georgia residents — local climate factored in.
OpenWater Intake — Hawaii
Daily water target for hawaii residents — local climate factored in.
OpenWater Intake — Idaho
Daily water target for idaho residents — local climate factored in.
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Choose the one that matches your situation from the grid above.
Enter a few details
Weight, activity, climate, species — takes under 30 seconds.
Get your target
A research-backed daily target plus an hourly schedule.
Learn the science behind human calculators
Read our in-depth guides for research-backed context on every calculator here.