The general consensus among experts is that a person can survive approximately 3 days without water, though estimates range from about 2 to 7 days depending on various factors

. This "rule of 3" is often cited: humans can live 3 minutes without air, 3 days without water, and 3 weeks without food

. Several factors influence survival time without water, including:

• Environmental conditions (heat, cold)
• Physical activity level
• Age and health status
• Body weight and composition
• Whether any water is obtained from food intake

In extreme heat or with physical exertion, dehydration can cause death within hours to a few days due to rapid fluid loss through sweating

. Conversely, in cooler, sedentary conditions, survival without water may extend toward the upper range of estimates, sometimes up to a week or slightly more

. Severe dehydration leads to symptoms such as extreme thirst, fatigue, organ failure, and ultimately death

. The kidneys and other organs fail without adequate hydration, and the body cannot perform essential functions like temperature regulation and cellular maintenance

. There are rare exceptional cases, such as an 18-year-old man who survived 18 days without food or water after being trapped, but these are extreme outliers and generally involve near-death states

. In summary, while the typical survival time without water is about 3 days, individual circumstances can shorten or lengthen this period, with a maximum usually not exceeding about a week under favorable conditions