Your Details

Enter your weight and activity level to estimate your hydration needs.

How This Calculator Works

This tool uses a simple hydration formula based on body weight and daily activity level.

Formula

  • Base Water: 35 ml Γ— body weight (kg)
  • Extra Water: 350 ml Γ— activity level
  • Total Water: Base + Extra

Example

If you weigh 70 kg and have moderate activity:

  • Base = 70 Γ— 35 = 2450 ml
  • Extra = 0.5 Γ— 350 = 175 ml
  • Total = 2625 ml β‰ˆ 2.63 liters

FAQ

Is this the same as the β€œ8 cups a day” rule?
No β€” this method adjusts for your weight and activity level.

Can I enter pounds?
Convert to kg first (lbs Γ· 2.205).

Does climate affect water needs?
Yes β€” hot climates require more water, but this calculator gives a general baseline.

Why Hydration Matters

Staying hydrated supports energy, focus, digestion, skin health, and overall well‑being. Your body’s water needs depend on your size, activity level, and environment β€” this calculator gives you a personalized estimate.

What This Tool Helps You Do

Who This Tool Is For

Additional FAQ

Does this include electrolytes?
No β€” this calculator focuses on water only.

Is this medical advice?
No β€” this is a general hydration estimate for everyday use.