Water Intake Calculator — your daily hydration target
Hydration needs scale with bodyweight, sweat rate and climate. This calculator starts from 35 ml per kilogram and adds for training volume and heat.
Calculate your water target
- Daily target
- 3.7 L
- Baseline
- 2.5 L
- Training add-on
- 600 ml
- Glasses (250 ml)
- 15
Results are estimates for general guidance and are not medical advice. See our medical disclaimer.
The baseline and the add-ons
A 70 kg adult starts around 2.45 litres a day. Every 30 minutes of hard training adds roughly 350 to 500 ml, and hot, humid conditions add another 500 ml or more.
Electrolytes matter in Indian summers
Sweating out two litres in Ahmedabad or Chennai costs you sodium and potassium as well as water. A pinch of salt and some lemon in one bottle, or an ORS sachet after a long session, restores what plain water cannot.
Reading your own signals
Pale straw urine, stable bodyweight across a session and no afternoon headache are better feedback than any formula. Log your intake in the habit tracker to see whether the target actually happens.
Frequently asked questions
Is 8 glasses a day enough?
Roughly two litres suits a small, sedentary adult in a cool climate. Larger, active people training in Indian heat often need three to four.
Does tea or coffee count?
Yes. Moderate caffeinated drinks contribute to daily fluid intake; they are not meaningfully dehydrating.
Can you drink too much water?
Yes, though rarely. Drinking litres in a short window without electrolytes can dilute blood sodium. Spread intake through the day.