VitalMath
100% on-device
Hydration goal
Build a practical daily fluid target from body weight, exercise duration and climate. Location is optional and interpreted only in this browser.
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Units
Your estimate
3.2litres/day
107 US fl oz · about 13 × 250 ml glasses
Weight baseline
2.6 L
35 ml per kg
Exercise allowance
0.5 L
350 ml per 30 minutes
Climate adjustment
+0 L
Selected climate
Mild
Includes fluids from drinks and water-rich foods. Needs rise with sweat, pregnancy or illness, while some heart/kidney conditions require clinician-set limits.
Educational estimates only—not medical advice, diagnosis or a substitute for a qualified clinician. Stop exercise and seek care for concerning symptoms.