How much water should I drink if I weigh 155 lbs?
For a moderately active 155 lb woman, the recommended daily water intake is approximately 100 fl oz (12.5 cups / 3.0L) per day. Your goal adjusts based on how active you are — see all levels below.
Moderate activity · no adjustments
100 fl oz
12.5 cups · 3.0L per day
Daily water intake at 155 lbs by activity level
No health considerations applied.
| Activity level | fl oz / day |
|---|---|
| Sedentary | 83 oz |
| Light | 93 oz |
| Moderate average | 100 oz |
| Very Active | 110 oz |
| Athlete | 124 oz |
Adjustments for health considerations
110 fl oz
100 oz + 10 oz pregnancy bonus · moderate activity
117 fl oz
100 oz + 17 oz breastfeeding bonus · moderate activity
How to reach 100 fl oz (12.5 cups) a day
Start with 16 oz before coffee
Drinking 16 oz (2 cups) of water first thing in the morning — before caffeine — starts your day 16% of the way to your 100 oz goal.
Break it into 13 cups
At 8 oz (one standard cup) per drink, you need 13 cups spread through the day — roughly one every 1–2 waking hours. Prefer a larger bottle? That's 7 pint-sized (16 oz) servings.
Log each drink as you go
Tracking in real time is significantly more accurate than trying to recall at night. Thirsty Girls' quick-log makes this a 2-second habit.
Drink 2 cups at 3pm
Most people hit a hydration wall in the mid-afternoon. A 3pm reminder to drink 16 oz (2 cups) before anything else can close 16% of your remaining gap in one go.
Hit your 100 oz goal every day
Thirsty Girls calculates your exact goal and tracks it — with AI coaching, smart reminders, and streaks that make it stick.
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