Water Tank Size Calculator

- Storage = daily use × days of storage
- Daily use = people × litres each + other uses
- Choose the next tank size up
- Supply interruptions decide how many days you need
On this page
Water Tank Size Calculator
Example figures only: replace them with your own. Results update as you type.
How Much Water Does a Person Use?
Use depends on whether the home has flushing toilets, showers and a washing machine. See how much water a family uses per day for a breakdown, and measure your own use from a water bill if you can.
How Many Days of Storage?
Match it to how often supply fails. If county water comes twice a week, store at least three or four days. Boreholes with a pump need less storage, but a reserve helps during power cuts.
Tank Sizes and Prices
500l Reliance water storage tankKSh 5,500
1000L Reliance Loft Tank – No More Water Shortages!KSh 12,500
1500L Water storage tankKSh 11,500
2000L Water storage tankKSh 16,500
3000L Water storage tankKSh 24,000
4000L Water storage tankKSh 27,500
5000L Reliance Water storage tankKSh 36,500
6000Ltrs Water Storage TankKSh 43,800
8000Ltrs Water Storage TankKSh 56,000
10,000Ltrs Water Storage TankKSh 68,000| Product | Price |
|---|---|
| 500l Reliance water storage tank | KSh 5,500 |
| 1000L Reliance Loft Tank – No More Water Shortages! | KSh 12,500 |
| 1500L Water storage tank | KSh 11,500 |
| 2000L Water storage tank | KSh 16,500 |
| 3000L Water storage tank | KSh 24,000 |
| 4000L Water storage tank | KSh 27,500 |
| 5000L Reliance Water storage tank | KSh 36,500 |
| 6000Ltrs Water Storage Tank | KSh 43,800 |
| 8000Ltrs Water Storage Tank | KSh 56,000 |
| 10,000Ltrs Water Storage Tank | KSh 68,000 |
Current listed prices incl. VAT (updated 4 October 2026).
Choose the next size up from the calculator. For refill shops see storage for refill stations; for the full list, tank price list.
Watch: Fabrication and components
Frequently asked questions
How do I calculate the size of a water tank?
Multiply your daily water use by the number of days of storage you want.
What size water tank does a family of 6 need?
At about 50 litres each plus other uses, around 400 litres a day; for three days, a 1,500-litre tank. Use your own figures.
How many litres of water does a person use per day?
It varies widely with toilets, showers and appliances; check your water bill or the guide linked above.
How many litres does my water tank hold?
For a round tank: 3.14 × radius² × height in metres × 1,000 gives litres; the size is also usually printed on the tank.
How much is a 10,000 litre water tank in Kenya?
Our 10,000-litre tank is KSh 68,000.
