Water Intake Calculator

Free daily water intake calculator based on your weight, activity level, and climate. Get personalized hydration recommendations in liters, cups, and fluid ounces. Includes hourly drinking schedule and dehydration warning signs.

Body Weight (lbs)

Activity Level

Climate / Environment

Special Factors (optional)

Enter your body weight above to calculate your recommended daily water intake in real time.

Signs of Dehydration

Dark Yellow Urine

Aim for pale straw color

Dry Mouth & Lips

Early sign of dehydration

Headache

Often caused by mild dehydration

Fatigue & Dizziness

Brain is sensitive to fluid loss

Decreased Urination

Less than 4 times per day

Dry Skin

Skin loses elasticity when dehydrated

Hydration Tips

Start Your Day with Water

Drink a glass of water first thing in the morning to rehydrate after sleep.

Drink Before Meals

Having water 30 minutes before meals aids digestion and helps control appetite.

Carry a Water Bottle

Keep a reusable bottle with you to encourage consistent sipping throughout the day.

Set Reminders

Use phone alarms or apps to remind yourself to drink water every hour.

Eat Water-Rich Foods

Fruits and vegetables like watermelon, cucumber, and oranges contribute to hydration.

Drink Before, During & After Exercise

Consume 7-10 oz every 10-20 minutes during physical activity.

Disclaimer

This calculator provides estimates based on general guidelines. Actual water needs vary based on individual physiology, health conditions, medications, diet, and other factors.

This is not medical advice. People with kidney disease, heart conditions, or those on fluid-restricted diets should consult their healthcare provider before adjusting water intake. Overhydration (hyponatremia) can be dangerous.

The 8-glasses-a-day rule is a simplified guideline. Your actual needs may be higher or lower. The best indicator of hydration is the color of your urine: pale straw color indicates good hydration.

How to Use Water Intake Calculator

1Enter your body weight.
2Select your activity level and climate.
3View your recommended daily water intake.
4Follow the hourly drinking schedule throughout the day.

Frequently Asked Questions

How much water should I drink per day?▾

A general guideline is half your body weight in ounces. A 160-lb person should drink about 80 oz (2.4 liters). This increases with exercise, hot weather, and altitude. Most adults need 2-3.5 liters per day.

Does coffee count toward water intake?▾

Yes, coffee and tea contribute to hydration despite being mild diuretics. The water content more than offsets the diuretic effect. However, water and herbal tea are the best choices for hydration.

What are signs of dehydration?▾

Dark yellow urine, thirst, dry mouth, fatigue, headache, dizziness, and decreased urine output. By the time you feel thirsty, you may already be mildly dehydrated.

About Water Intake Calculator

NexTool's Water Intake Calculator is completely free to use with no sign-up required. Your data is processed directly in your browser and never sent to our servers, ensuring complete privacy and instant results.