Water tank size calculator
Calculate the right water tank size for your home from the number of residents, use per person and days of reserve.
What size water tank should I buy?
Everything happens on your device: nothing is uploaded to the internet.
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Water tank size calculator: what it is for
Enter how many people live in the house, the daily use per person and for how many days you want a reserve. The calculator shows the capacity needed, suggests the nearest standard tank and calculates daily and monthly use.
Useful for new builds, renovations and anyone who deals with water shortages.
How to use
- Type the number of residents.
- Adjust the use and the days of reserve.
- See the capacity and the suggested tank.
When to use it
- Buy a water tank for a new house.
- Plan a reserve in areas with rationing.
- Estimate the family's water use.
Frequently asked questions
How much water does a person use per day?
In homes, use usually runs between 150 and 200 liters (40 to 50 gallons) per person per day, including showers, toilets, cooking and cleaning. Homes with a garden or pool use more.
How many days of reserve should I have?
The most common is to store water for 1 to 2 days. In areas with frequent water shortages, plan for 3 days or more, split into two tanks.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.