WaterDailyGoal
Our planning method and named sources

How much water should you actually drink?

Skip the vague “8 glasses” rule. Get your personal daily water goal in seconds — from your body, your activity, and your climate.

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Quick startPick a day type
Used for the base estimate
Activity level
ClimateWhere you spend your day
Fine-tuneMeasure in bottles · Your day
Life stageOptional
Measure in bottlesOptional
Optional — see what's left
glasses
Your dayShapes the sip schedule

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Your daily goal: 2.6 litres, 10.5 glasses.

Your daily goal

Updates instantly
2.6litres

of water a day · about 10.5 glasses · 5 half-litre bottles

Planning scenarios: 2.4-3.1 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

2.6
Litres
88
Ounces
10.5
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 methodology

Next step

Your sip schedule

  • 7:00 AM · Start the day2 glasses
  • 9:48 AM · Top up2 glasses
  • 12:36 PM · Top up1.5 glasses
  • 3:24 PM · Top up1.5 glasses
  • 6:12 PM · Top up1.5 glasses
  • 9:00 PM · Wind down1.9 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

2.6 litres

The link and preview image include your weight and settings.

Example: a 70 kg moderately active adult in a temperate climate has a daily water goal of about 2.6 litres (88 fluid ounces, roughly 10.5 glasses).

Quick answer

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. A 70 kg adult with light activity in a temperate climate gets 2.6 L in this model.

Maintained by the WaterDailyGoal TeamLast updated Editorial update; not a medical review.

What shapes your number

Body weight

Our starting assumption is 33 ml/kg; it is not a validated individual requirement.

Activity

Every hard hour of training adds fluid lost as sweat, so athletes need noticeably more.

Climate

Heat and humidity push sweat losses up; we add about 10% for hot, humid days.

Life stage & meds

Pregnancy, breastfeeding, and medication need individual clinical advice. These flags add context without prescribing extra water.

Frequently asked

How much water should I drink a day?

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.

Is the 8 glasses a day rule accurate?

It is a decent rough guess, but it ignores body size and activity. A personal estimate based on weight and daily conditions is usually more useful.

Do coffee, tea, and food count?

Yes. Coffee and tea still contribute fluid, and food usually adds roughly 20% of your total water intake.