Tank Volume Calculator
Select the style of tank and its dimensions to calculate the capacity in gallons and liters. Optionally, enter the filled depth to calculate the volume of liquid in a tank.
Calculate Horizontal Cylinder Tank Volume
Calculate Vertical Cylinder Tank Volume
Calculate Horizontal Oval Tank Volume
Calculate Vertical Oval Tank Volume
Calculate Horizontal Capsule Tank Volume
Calculate Vertical Capsule Tank Volume
Calculate Rectangular Tank Volume
Calculate Sphere Tank Volume
Tank Volume Estimate:
Filled Volume
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Joe is the creator of Inch Calculator and has over 20 years of experience in engineering and construction. He holds several degrees and certifications.
How to Calculate Tank Volume
You can find the volume or capacity of a tank in a few easy steps. Of course, the calculator above is the easiest way to calculate tank volume, but follow along to learn how to calculate it yourself.
Step One: Measure the Tank
The first step is to measure the key dimensions of the tank. For round tanks, find the diameter and length or height. For rectangular or cubes, find the length, width, and height.
Step Two: Find the Tank Volume Formula
In order to calculate a tank’s capacity, you’ll need a formula for volume. The volume formula varies for each style of tank. See the formulas below and select the one for your style.
Cylinder Tank Formula
tank volume = π × r2 × l
r = radius (diameter ÷ 2)
l = length (or height for a vertical tank)
Oval Tank Formula
area = ((h – w) × w) + (π × r2)
tank volume = area × l
r = radius (tank width ÷ 2)
w = width
l = length
h = height
Capsule Tank Formula
cylinder volume = π × r2 × l
sphere volume = 4/3 π × r3
tank volume = cylinder volume + sphere volume
r = radius (diameter ÷ 2)
l = length (or height for a vertical tank)
Rectangular Tank Formula
tank volume = l × w × h
l = length
w = width
h = height
Not finding a formula for the shape of your tank? Find even more volume formulas.
Step Three: Solve the Volume Formula
When you have the tank dimensions and the appropriate formula to solve for volume, simply enter the dimensions into the formula and solve.
For example, let’s find the volume of a cylinder tank that is 36″ in diameter and 72″ long.
radius = 36″ ÷ 2
radius = 18″
tank volume = π × 182 × 72
tank volume = 73,287 cu in
Thus, the capacity of this tank is 73,287 cubic inches.
Step Four: Convert Volume Units
The resulting tank volume will be in the cubic form of the initial measurements. For instance, if the initial tank measurements were in inches, then the volume measurement would be in cubic inches.
You’ll often need the volume in another form, such as gallons or liters.
Thus, the final step is to convert from one volume measurement to the desired unit of the result. Try our volume converter to convert the results to gallons, liters, or any other unit.
Curious how much a tank full of water weighs? Calculate it using our water weight calculator.