How long can you survive without water? Surviving without water varies based on factors like age, health, and environmental conditions. Generally, humans can survive for about three to five days without water, but this timeframe is highly variable and depends on individual factors. Dehydration sets in quickly, leading to organ failure and death. It's crucial to prioritize hydration for survival, as water is essential for bodily functions like temperature regulation, digestion, and waste elimination. In extreme conditions, the body's survival mechanisms may prolong life temporarily, but water remains indispensable for sustaining life.