Daily Water Intake Calculator

Calculate how much water you should drink over the course of each day based on your weight

About This Tool

Proper hydration is critical for almost every bodily function. This includes temperature regulation, moving your joints, nutrient transport, and waste elimination. Taking too little (or too much) fluids can have serious health impacts. You should aim to drink regularly throughout the day to keep pace with your body's needs.

Your daily water needs vary with your weight, activity level, climate, and your health status. A common guideline suggests you get roughly 35 millilitres of water per kilogram of body weight (or, about half an ounce per pound) every day. This calculator uses that rule of thumb to generate a personalized baseline target for your water intake.

By meeting this target, you support optimal cellular function, stable mood, clearer thinking, and sustained physical endurance. Use this estimate as a starting point and adjust for factors like exercise, heat, or medical recommendations.

Remember that your actual needs may shift based on activity intensity, ambient temperature, altitude, diet, and overall health. Tracking urine colour (should be almost colourless), thirst cues, and general wellbeing can help you fine-tune hydration. Always consult a healthcare professional for specific medical or performance-related hydration advice depending on your activities.