70 kg, moderate activity, temperate
Input Weight 70 kg, 3–5 workouts a week, temperate climate.
Result 2,730 ml a day — about 2.73 L, 11.4 cups or 5.5 bottles.
Daily Water Intake Calculator
Everyday LifeTurn body weight, activity level and climate into a daily water target in millilitres, litres, cups and bottles.
Your inputs
Result
Daily water target
—
ml
- In litres — L
- Cups (240 ml) —
- Bottles (500 ml) —
Change any input and the result updates instantly.
Formula and rules
- Base intake = body weight in kg × 30 ml
- Activity factor: 1.0 sedentary, 1.15 light, 1.3 moderate, 1.45 high
- Climate factor: 1.0 temperate, 1.1 warm, 1.2 hot or humid
- Daily target = base × activity factor × climate factor
- About 20% of daily water normally comes from food, so drinks can be slightly lower
Worked examples
85 kg, high activity, hot climate
Input Weight 85 kg, daily training, hot or humid climate.
Result 4,437 ml a day — about 4.44 L, 18.5 cups or 8.9 bottles.
154 lb, light activity, warm climate
Input Weight 154 lb, 1–2 workouts a week, warm climate.
Result About 2,651 ml a day — 2.65 L, 11.0 cups or 5.3 bottles.
FAQ
Is the 8 glasses a day rule accurate?
It is a rough average, not a rule. Needs scale with body size, sweat losses and climate, which is why a 55 kg office worker and an 85 kg outdoor worker should not share the same target.
Do tea, coffee and soup count?
Yes. All drinks contribute, and food adds roughly another fifth. Strong caffeine and alcohol have a mild diuretic effect but still count towards the total.
Can I drink too much water?
Rarely, but drinking several litres within a short time can dilute blood sodium. Spread intake across the day, and follow medical advice if you have kidney, heart or liver conditions.
Disclaimer: Results follow the formula shown on this page and are for reference only. Real-world quantities vary with materials, technique and conditions, so allow a margin before ordering.