70 kg with 30 minutes of exercise
70 × 0.035 + (30 ÷ 30) × 0.35 = 2.45 + 0.35 = 2.8 litres.
Daily water intake calculator
Estimate daily water intake from body weight and activity.
Calculation details
Change the values to update the result instantly.
How it works
Estimate daily water intake from body weight and activity. This free estimate is for planning purposes. Verify financial and tax decisions with a qualified professional.
How daily water intake is estimated
The calculator combines body weight and exercise time: litres = weight (kg) × 0.035 + (exercise minutes ÷ 30) × 0.35.
No exercise on a given day
With 0 minutes of exercise, only the weight-based portion applies: 70 × 0.035 = 2.45 litres.
More exercise increases the estimate
Each additional 30 minutes of exercise adds another 0.35 litres to the total.
Frequently asked questions
How is daily water intake estimated?
It combines body weight (weight × 0.035) with an exercise adjustment (exercise minutes ÷ 30 × 0.35).
Does exercise change the estimate?
Yes. Every 30 minutes of exercise entered adds another 0.35 litres to the estimate.
What does the daily water intake calculator calculate?
Estimate daily water intake from body weight and activity.
Is this calculator free to use?
Yes. You can change the values and calculate as often as you need without creating an account.
How accurate is the result?
The result is an estimate based on the values you enter. Rates, fees, taxes and personal circumstances can change the final amount.