All calculatorsSwitch tool

Water Intake Calculator

Estimate how much water you need each day from your body weight and training time.

Your inputs

Current weightkg

Activity & goal

Training per daymin

The formula

Body-Weight Hydration Guideline

Baseline
baseline(L) = weight(kg) × 0.035
Training addition
training addition(L) = training minutes × 0.012

No single inventor; derived from sports-science hydration guidelines · Guidelines refined since the 1990s–2000s

Result

Daily water estimate

3.2 L

Body-weight baseline plus your training-duration estimate.

Training addition

0.5 L

Added from the minutes you train per day.

Hydration needs shift with body weight, sweat rate, climate, sodium intake, and training duration.

Use thirst, urine color, sweat rate, and performance as practical checks.

Results are estimates from published formulas, intended for healthy adults. They aren't medical advice, so check with a doctor or registered dietitian if you have a health condition.