The most common answer of 8-10 glasses a day is not a bad answer. The real problem with it is that it is not a one-size-fits-all question. A good goal is to drink 1/2 ounce for every pound you weigh. So if you weigh 180 lbs you should drink 90 ounces of water each day … as a general rule. In reality your body needs more water than this per day. Fortunately, not all of our water consumption needs to come from drinking it. The amount of H20 you get per day (another general rule) should be about 125 ounces a day for men and about 90 ounces a day for women. This does not mean that you need to drink this much water. Our food is made up greatly of water.