WebMD cites the common recommendation advising people to drink six to eight 8-ounce glasses of water or fluids a day. The specific amount varies depending on such factors as climate, the person's exercise level and whether or not she is sick.
Mayo Clinic recommends 13 cups of fluid a day for men and 9 cups for women. This translates to 104 ounces daily for men and 72 for women. It points out that the advice to drink eight 8-ounce glasses of water daily is generally sound and is helpful because it is easy to recall; however, people need to remember that total consumption includes all fluids, not just water.