Estimate how much water and electrolytes you need to safely rehydrate after early or mild dehydration
Finish your rehydration estimate, then use one of these next steps to reduce bounce and keep people moving through the site.
70 kg (154.3 lbs)
Selected: Level 3 - Yellow – Normal hydration
Typical: 3-4 hours when hydrated
Adds +0.5L for fluid loss compensation
Display hydration plan (mL per 15 min)
Most adults need about 1–2 L water and electrolytes to recover from mild dehydration. The exact amount depends on your body weight, symptoms, and degree of dehydration.
Yes — rehydrate slowly. Sip 200 mL every 15 minutes to prevent nausea or electrolyte imbalance. Drinking too much too fast can cause water intoxication.
Electrolytes (sodium and potassium) help your body retain water and maintain proper cellular function. Plain water alone can dilute your blood sodium levels.
Seek immediate medical care if you experience severe symptoms like vomiting, confusion, fainting, or haven't urinated for over 8 hours. This calculator is for mild to moderate dehydration only.
• WHO Oral Rehydration Solution Guidelines, 2023
• EFSA Scientific Opinion on Dietary Reference Values for Water, 2022
• Sawka MN, et al. Journal of Applied Physiology (2015): Body water and health
• Popkin BM, et al. Nutrition Reviews (2010): Water, hydration, and health
• Mayo Clinic (2024): Dehydration – symptoms and treatment
Stay hydrated — check your daily water needs with our main calculator
Hydration Calculator