The amount of water you should drink daily varies based on factors such as age, sex, activity level, climate, and physiological conditions like pregnancy or breastfeeding. Here are general guidelines:

• Adult men (19 years and older): Approximately 3.7 liters (about 125 ounces or 13 cups) of total fluids per day, with about 3 liters (104 ounces or 13 cups) from beverages

• Adult women (19 years and older): Approximately 2.7 liters (about 91 ounces or 9 cups) of total fluids per day, with about 2.2 liters (72 ounces or 9 cups) from beverages

• Children: Intake varies by age, for example:
  • Ages 4–8: 40 ounces (5 cups)
  • Ages 9–13: 56–64 ounces (7–8 cups)
  • Ages 14–18: 64–88 ounces (8–11 cups)

• Pregnant women: Around 80 ounces (10 cups) of water daily

• Breastfeeding women: Around 104 ounces (13 cups) daily

The common advice to drink eight 8-ounce glasses (64 ounces) per day is a reasonable starting point but may not meet everyone's needs, especially for those who are physically active, live in hot climates, or have specific health conditions

. A practical approach is to listen to your body's thirst signals and adjust intake accordingly, ensuring you stay well-hydrated throughout the day

. Additionally, about 20% of your daily fluid intake typically comes from food, with the rest from drinks

. For a personalized estimate, you can use a simple formula: multiply your weight in pounds by 0.67 to get the minimum ounces of water you should drink daily, then add 12 ounces for every 30 minutes of exercise

. In summary, while general recommendations are around 91–125 ounces (9–13 cups) of fluids daily for adults, individual needs vary and should be adjusted based on lifestyle and environmental factors.