Daily Water Intake for a 90 kg Active Person
An active 90 kg individual should aim for approximately 3.4–4.0 litres of water per day.
How to use this tool
- Enter body weight and activity level in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your water per day and the full breakdown beneath it.
Larger body mass combined with regular exercise creates significantly higher hydration demands.
Frequently asked questions
- How much water should I drink per day?
- The NHS recommends 6–8 cups (1.5–2 L) daily. The 35 ml/kg rule adjusts this for body size and is widely used by dietitians.
- Does coffee or tea count towards water intake?
- Yes — caffeinated drinks count towards hydration despite mild diuretic effects. Fruit and vegetables also contribute significant water.