The volume of water in one glass can vary depending on the size and type of glass being used. However, a standard glass of water is often considered to be approximately 240 milliliters (mL), which is equivalent to about 8 fluid ounces. This is a common reference for a typical serving of water in many contexts. It’s important to note that the size of a glass can vary, so the volume of water in a glass may not always be exactly 240 mL, but this is a commonly used approximation.