Per kilogram
How Much Water Should a 80 kg Person Drink?
Quick answer
A 80 kg (176 lb) adult has a site planning estimate of 2.9 litres (98 fl oz, or 11.5 glasses) of beverages a day at a light activity level in a temperate climate. Site scenarios range from 2.5 litres on a quiet, cool day to about 3.6 litres with active activity and hot climate. These are planning assumptions, not medical requirements.
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Your daily goal: 2.9 litres, 11.5 glasses.
Your daily goal
Updates instantlyof water a day · about 11.5 glasses · 6 half-litre bottles
Planning scenarios: 2.7-3.5 litres. Use it as a flexible target, not a medical limit.
Start
2 glasses
7:00 AM
Taper
9:00 PM
for better sleep.
Food fluid
+0.7 L
typical food water
- 2.9
- Litres
- 98
- Ounces
- 11.5
- Glasses
Why this number
WaterDailyGoal uses 33 ml/kg for a beverage planning estimate. The 30–40 ml/kg scenarios and activity/climate coefficients are site assumptions, not validated personal requirements or NAM/EFSA formulas. Pregnancy, breastfeeding, and GLP-1 medicines do not automatically change this estimate. Population total-water references include food; they are not minimum drinking doses. Follow individual clinical advice.
Full methodologyNext step
Your sip schedule
- 7:00 AM · Start the day2 glasses
- 9:48 AM · Top up2 glasses
- 12:36 PM · Top up2 glasses
- 3:24 PM · Top up2 glasses
- 6:12 PM · Top up2 glasses
- 9:00 PM · Wind down1.6 glasses
Ease off after 9:00 PM for better sleep.
Electrolytes? Not automatic
Electrolytes are not automatic. Long or heavy sweating and vomiting or diarrhea need different approaches; food, losses and medical restrictions matter. Ask a clinician or pharmacist when illness is involved.
A friendly estimate for healthy adults, not medical advice. Your needs rise with heat, exercise, illness, pregnancy, and some medications. Don't drink more than ~1 litre per hour.
Daily goal
2.9 litres
The link and preview image include your weight and settings.
How much water is that? A 80 kg breakdown
For a 80 kg (176 lb) adult, the daily drinking goal lands near 2.9 litres (98 fl oz) at a moderate activity level. That's about 11.5 glasses or 6 half-litre bottles. On a quiet, cool day you might need as little as 2.5 litres; on an active day in the heat, closer to 3.6 litres.
| Body weight | Litres | Ounces | Glasses |
|---|---|---|---|
| 70 kg | 2.6 | 88 | 10.5 |
| 75 kg | 2.8 | 95 | 11 |
| 80 kg | 2.9 | 98 | 11.5 |
| 85 kg | 3.1 | 105 | 12.5 |
| 90 kg | 3.3 | 112 | 13 |
Compare day assumptions
Quiet / cool
2.5 L
Light activity / temperate
2.9 L
Active / hot
3.6 L
| Bottle size | Full bottles | Final partial bottle |
|---|---|---|
| 500 ml | 5 | 400 ml |
| 710 ml | 4 | 60 ml |
| 1000 ml | 2 | 900 ml |
| 1183 ml | 2 | 534 ml |
Where the 80 kg number comes from
The site estimate for 80 kg starts with 80.00 kg × 33 ml/kg, then adds 300 ml for light activity and uses a temperate-climate factor of 1.0. That gives 2.9 L after rounding, including the activity adjustment. NAM and EFSA do not prescribe this per-weight formula.
Compare a sedentary, cool scenario (2.5 L) with an active, hot scenario (3.6 L). These are calculator assumptions, not personal minimums or maximums. Use measured sweat losses for sport and individual clinical advice for pregnancy, medication or illness; do not stack extra half-hour allowances on top of these numbers.
Don't drink it all at once
Plan regular access to drinks without forcing the daily estimate. A schedule is a reminder, not a medical rule. Pale urine is only one clue; thirst, recent losses, symptoms and clinical restrictions also matter.
Plan drinks for 80 kg
Add your real activity, climate, and life stage to dial in a goal made for you — not just your weight.
Frequently asked
How much water for 80 kg?
A 80 kg (176 lb) adult has a site planning estimate of 2.9 litres (98 fl oz, or 11.5 glasses) of beverages a day at a light activity level in a temperate climate. Site scenarios range from 2.5 litres on a quiet, cool day to about 3.6 litres with active activity and hot climate. These are planning assumptions, not medical requirements.
How many glasses is 2.9 L?
2.9 L is about 11.5 glasses of 250 ml or 6 bottles of 500 ml. These are rounded container equivalents, not additional water.
Is the 80 weight result a required amount?
No. 2.5 L for a sedentary cool scenario and 3.6 L for an active hot scenario are site estimates. Real losses and clinical instructions can differ. The model uses 33 ml/kg, not a validated NAM or EFSA body-weight prescription.