Pipe Volume Calculator

Calculate volume instantly from inner diameter and length — shows liters, gallons and mass.

Auto-fill diameter for standard pipe sizes

Use the pipe bore (not outer diameter).

Total length of the pipe segment.

Default: water (997 kg/m³). Enter custom density if needed.

Worked Example

Let’s calculate the volume of a 2-inch diameter pipe that’s 10 feet long.

Inputs:
Inner diameter (d) = 2 inches
Length (L) = 10 feet
Step 1: Convert to consistent units (meters)
d = 2 in × 0.0254 = 0.0508 m
L = 10 ft × 0.3048 = 3.048 m
Step 2: Calculate radius
r = d/2 = 0.0508/2 = 0.0254 m
Step 3: Apply volume formula
V = π × r² × L
V = 3.14159 × (0.0254)² × 3.048
V = 0.006189 m³
Step 4: Convert to common units
Liters: 0.006189 × 1000 = 6.19 L
US Gallons: 0.006189 × 264.172 = 1.63 gal
Imperial Gallons: 0.006189 × 219.969 = 1.36 gal

Frequently Asked Questions

Should I use inner or outer diameter for pipe volume?
Always use the inner diameter (bore) of the pipe when calculating volume. The calculator assumes the pipe is completely filled. The outer diameter includes the pipe wall thickness and would give you an incorrect volume.
How do I convert the result to gallons or liters?
The calculator automatically displays results in multiple units: liters, cubic meters, US gallons, Imperial gallons, and cubic feet. All conversions appear instantly below the main result.
What is nominal pipe size and how does it relate to inner diameter?
Nominal pipe size is a standardized designation that doesn’t always match the actual inner diameter. For example, a “2-inch nominal” pipe typically has an inner diameter of about 52.5mm (2.067 inches). Use our presets dropdown to auto-fill the correct inner diameter for common nominal sizes.
How do I measure the pipe bore accurately?
Use calipers or a ruler to measure the inside diameter directly at the pipe opening. For installed pipes where you can’t access the end, consult manufacturer specifications or look for markings on the pipe that indicate the schedule and nominal size, then reference a pipe dimension chart.
What density should I use for different fluids?
Common fluid densities: Water is 997 kg/m³ (default), light oil approximately 850 kg/m³, sewage 1000-1050 kg/m³, diesel fuel about 832 kg/m³, gasoline around 750 kg/m³. For precise calculations with other materials, look up the specific density value for your substance at the operating temperature.
Does this calculator assume the pipe is completely full?
Yes, the calculator assumes the pipe is 100% filled with the material. For partially filled pipes (like gravity-fed drainage), you would need to calculate the cross-sectional area of the fluid segment separately and multiply by length. This is more complex and depends on the fill level.
Can I use this for rectangular or non-circular pipes?
No, this calculator is specifically for cylindrical (circular) pipes. For rectangular ducts or channels, you would calculate volume as width × height × length. For other shapes, use the appropriate cross-sectional area formula.
Why do I need to know the pipe volume?
Knowing pipe volume is essential for various applications: estimating how much liquid needs to be drained, calculating chemical treatment dosages for water systems, sizing pumps and tanks, determining heating/cooling requirements for pipe contents, and planning material quantities for construction projects.