This water calculator can help you estimate the amount of water you should drink as daily requirement so you don’t have to worry how much water you need. More info on this topic you can find below the form.

Weight: *
Activity Level: *
Age: *
Weight: *
Activity Level: *
Age: *

How does the water calculator work?

This tool can prove to be very useful in determining how much water you actually need to drink as it takes various factors in consideration.

As we all know, there are many contradictions when it comes to the subject of water and everyone seems to have a different opinion.

The common sense advice would be to follow your body and see what it requires but in the same time start with some guidelines that can reflect your state.

For instance, this water calculator asks you to provide your weight, in either English or metric and your level of activity and age. Within the activity level you can choose from Sedentary, Moderately active, Active and Highly active.

Once you press calculate you will be given the amount of water you need in various measurements so it includes the units you feel most comfortable with.

Example calculation:

For a female, aged 35, weighing 165 lbs and with a moderately active lifestyle, the daily water intake is of around 107.3 ounces or approximately 3.2 liters or 13.4 cups.

If she would become highly active and maintain her weight then she would probably require more water, around 132 ounces per day. You can calculate as many situations as you like by pressing calculate again.

Why is water intake so important?

Water is essential for the body to work properly. Daily water intake must be calculated according to the weight and lifestyle of each person as it is important that the body receives the right amount of fluids for his needs.

Meeting your daily water requirements will keep you away from dehydration, increase your performance and even take you on the way to a healthier, leaner body

The total fluid intake consists of water, other beverages drunk and water from foods eaten. According to the Institute of Medicine, about 80 percent of the water you consume each day comes from water and beverages, and about 20 percent is derived from the foods.

When you know the daily water consumption, you can also calculate the hourly water requirement by dividing the amount obtained to the hours you are awake during day. For example an active 150 pound person that sleeps 8 hours per night should drink 8 oz water every hour.

How about children’s water intake?

The water calculator can even estimate how much water a child should drink. This is a sensible issue as a proper level of hydration helps the kid develop properly, maintain a healthy weight and good concentration levels.

This is why it is very important to keep track of the fluid intake of the child. Especially because the little ones don't always ask for water, by the time a toddler realizes he is thirsty he may already be mildly dehydrated.

A child's daily intake of fluids varies with age, weight and gender, temperature, activity levels and overall health condition.

What if it’s too little or too much?

Knowing exactly what your body wants is essential otherwise you can fall on either side. You might drink too little water and be prone to dehydration, with symptoms like headaches, fatigue, heartburn or lack of concentration.

Or you might have too much water and have a risk to develop hyponatremia or water intoxication that triggers cell ruptures in different parts of the body and symptoms like vomiting, headaches, confusion and later seizures and coma.


1) Montain SJ, Cheuvront SN, Carter R, Sawka MN. (2006) Human Water and Electrolyte Balance.

2 Sawka M, et al. Human water needs. Nutrition Reviews 2005;63:S30.

13 Dec, 2014