Hydration Check Calculator
Check your hydration status from urine color, activity level, and temperature.
Get a clear reading plus how much extra water to drink for exercise and heat.
This tool reads your hydration from urine color, the most reliable real-time indicator, then adds how much extra water to drink for your activity level and the heat.
Urine color scale (1–8):
- 1 Clear to 3 Light yellow: well hydrated. Clear all day can mean slightly over-hydrated.
- 4 Yellow: mildly dehydrated. Drink a glass or two now.
- 5 to 6 Dark yellow to amber: dehydrated. Drink water soon.
- 7 to 8 Dark amber to brown: severely dehydrated, or a possible medical issue worth checking.
Extra water for activity and heat (added to your normal intake):
- Lightly active: +500 mL
- Moderately active: +750 mL
- Intense exercise: +1,000 mL
- Moderate heat (70–85°F): +250 mL
- Hot (above 85°F): +500 mL
Electrolyte consideration: For activity over 60 minutes at moderate-to-high intensity, water alone is not enough. Sodium (500–700 mg/hour), potassium, and magnesium are lost in sweat and should be replaced.
Reference: total daily fluid (Institute of Medicine):
- Men: about 3.7 liters (125 oz) per day, including all beverages and food moisture
- Women: about 2.7 liters (91 oz) per day
- Pregnant women: about +10 oz; breastfeeding: about +13 oz
- Roughly 20% of daily fluid comes from solid food
For a weight-based daily target in ounces, use the Water Intake Calculator linked below. This page is a quick status check, not a full intake plan.
How we build and check this calculator
This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.