Overhead Tank Volume Calculator

Calculate the capacity of your overhead water tank in liters or gallons

Calculation Results

Tank Shape:
Dimensions:
Volume:

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Frequently Asked Questions

How accurate is this overhead tank volume calculator? +

Our calculator provides highly accurate results based on standard geometric formulas. For rectangular tanks, it uses length × width × height, and for cylindrical tanks, it uses π × radius² × height. The results are precise for standard tank shapes, but actual capacity may vary slightly due to manufacturing variations.

What’s the difference between liters and gallons? +

Liters and gallons are both units of volume measurement. 1 US gallon equals approximately 3.785 liters. Our calculator automatically converts between these units, with the US gallon (not imperial gallon) as the standard for the gallons option.

How do I measure my tank dimensions correctly? +

For rectangular tanks: measure the interior length, width, and height from the bottom to the overflow level. For cylindrical tanks: measure the interior diameter (distance across the circular base) and height. Always measure in a straight line, not following the curves of the tank.

Why is knowing my tank volume important? +

Knowing your tank’s volume helps with: proper water treatment dosing, understanding water usage patterns, planning for emergency storage needs, sizing replacement tanks, and ensuring your water pump has adequate capacity to fill the tank efficiently.

Can I use this calculator for underground or horizontal tanks? +

Yes, the same volume calculations apply regardless of tank orientation (vertical/horizontal) or placement (overhead/underground). However, for horizontal cylindrical tanks, the actual water volume at different fill levels requires more complex calculations.