each glass counts as 250ml · saved on this device only
Your hydration streak
Days where you reached your goal are shown in green.
How it works
Enter your weight and activity level. More activity means more fluid loss, so the goal adjusts upward.
Get your daily goal. The calculator uses a common formula — roughly 33ml per kg of bodyweight — then scales it by your activity level.
Log glasses as you drink. Tap the + button each time you finish a glass (counted as 250ml). The progress bar fills up toward your goal.
It resets daily. Your tracker automatically starts fresh each day, while your goal stays saved.
This is a general estimate — actual needs vary with climate, exercise intensity, health conditions, pregnancy, and medications.
Frequently asked questions
A common estimate is about 33ml per kg of body weight per day, adjusted upward for activity level — this calculator gives you a number based on your own weight and activity rather than a generic "8 glasses" rule.
Yes — more activity means more fluid loss through sweat, so the calculator scales your goal up based on your selected activity level.
It's a reasonable rough average for many adults, but actual needs vary by body size, climate, and activity — a calculation based on your own numbers is more accurate than a one-size-fits-all rule.
Yes — after calculating your goal, use the tap counter below it to log each glass (250ml) and watch your progress bar fill up.
Most research suggests moderate caffeinated drinks do contribute to hydration, though plain water is still the most reliable way to track your intake with this calculator.
Yes — choose from 200ml, 250ml, 330ml, 500ml, or 750ml in the tracker, matching whatever cup or bottle you're actually using. Your goal automatically converts to the right number of taps.
Yes — a streak badge shows how many consecutive days you've reached your water goal, and a weekly chart shows the last 7 days so you can see your pattern at a glance.
Yes, fluid needs generally increase during pregnancy and especially while breastfeeding. This calculator gives a general baseline for healthy adults — talk to your doctor or midwife for guidance specific to your pregnancy.
This is a general estimate, not medical advice. Needs vary with climate, health conditions, pregnancy, and medications — check with a doctor if you have specific concerns.