Daily Water Intake Calculator

Get your science-backed daily water intake recommendation based on your body, lifestyle, and environment.

Your Details

Age (years) Gender Body Weight

Activity Level Climate

Your Recommendation

Recommended daily intake: -

Beverages: -

From food (~20%): -

Beverages (~80%) Food (~20%)

-

Liters

-

Fluid Ounces

-

Cups (8 oz)

-

Glasses (250 ml)

Based on National Academies of Sciences Adequate Intake (AI), adjusted for weight, age, activity, and climate.

Hydration Benefits

Supports temperature regulation and physical performance.
Helps maintain focus, mood, and energy levels.
Aids digestion, circulation, and kidney function.
Helps skin elasticity and joint lubrication.

Food-Based Water Sources

Fruits: watermelon, oranges, strawberries, grapes.
Vegetables: cucumber, lettuce, celery, tomatoes.
Other foods: soups, broths, yogurt, and oatmeal.
These foods can contribute roughly 20% of your daily water needs.

Activity Adjustment Tips

Drink 500-750 ml (17-25 oz) extra for every hour of moderate exercise.
Hydrate before, during, and after workouts in warm weather.
Check urine color: pale yellow usually indicates good hydration.
Increase intake gradually when activity level or heat exposure rises.

Hydration Guide

National Academies Reference

The National Academies of Sciences sets Adequate Intake (AI) at about 3.7 L/day for men and 2.7 L/day for women from all beverages and food. Roughly 80% from drinks and 20% from food.

How This Calculator Works

Blends NAS population AI with weight-based estimate (~35 ml/kg total water).
Gender and age factors adjust baseline needs.
Activity level adds sweat-related fluid requirements.
Climate factor adjusts for heat, humidity, or cold environments.

Practical Daily Targets

Carry a reusable bottle and sip regularly throughout the day.
Drink more during travel, altitude changes, illness, or pregnancy (consult your doctor).
Balance water with electrolytes during long or intense sessions.
Listen to thirst signals and adjust based on how you feel.

All calculations are done in your browser. No data is stored or shared.