Pipe Weight Calculator OD, wall and material
Enter the outside diameter, wall thickness, length and material. Works in millimetres and metres for kilograms, or inches and feet for pounds.
Outside Diameter, Not Nominal
Empty Pipe Only
How do you calculate pipe weight?
At a Glance
Take the cross-section of the wall — a hollow circle — multiply by the length, and multiply by the material density: weight = π/4 × (OD² − ID²) × length × density, where the inside diameter is the OD minus two wall thicknesses.
A pipe is a tube, so its cross-section is a ring: the full circle minus the bore. The bore diameter is the outside diameter minus the wall on both sides — that factor of two is the step people most often skip.
With the ring area in square metres and the length in metres you have a volume, and density turns volume into mass. The densities used here:
| Material | Density (kg/m³) |
|---|---|
| Carbon steel | 7,850 |
| Stainless steel 304 | 8,000 |
| Cast iron | 7,200 |
| Copper | 8,960 |
| Brass | 8,500 |
| Aluminium | 2,700 |
| PVC | 1,400 |
weight = π ÷ 4 × (OD² − ID²) × length × density, ID = OD − 2 × wallThese are the values the calculator loads by default.
Find the inside diameter
60.3 − 2 × 3.91 = 52.48 mm. The wall comes off both sides, which is why it is doubled.
Take the ring cross-section
π/4 × (0.0603² − 0.05248²) = 0.000693 m² of steel in the wall.
Multiply by the length
0.000693 × 6 = 0.004156 m³ of material.
Apply the density
0.004156 × 7,850 = 32.6 kg, or 5.44 kg per metre — the figure printed in the pipe schedule.
The number is the bare pipe, empty. For anything structural you usually need more than that.
Contents matter more than you expect. That same DN50 pipe holds about 2.2 litres per metre. Full of water it is 7.6 kg/m rather than 5.44 — a 40 % increase, and the figure your supports have to carry.
Fittings, flanges and valves are not in here. A single DN50 flange can weigh more than a metre of the pipe it bolts to. So can a valve. For a bill of materials, count them separately.
Per-metre is the useful unit for pricing. Set the length to 1 to get the rate, then scale — that is also how you compare against a supplier's schedule table. To go from weight back to volume, Cylinder Volume Calculator and Density Calculator cover the other directions.
Nominal dimensions, nominal densities
Two sources of error stack here, and both run the same way.
Manufacturing tolerance on wall thickness is typically −12.5 % on seamless pipe, so a nominal 3.91 mm wall may legitimately be 3.42 mm — around 12 % less steel than this calculates. Densities are standard values too: carbon steels run 7,800 to 7,900 kg/m³ depending on the alloy, stainless grades 7,900 to 8,050.
Treat the result as a nominal figure good to a few percent, which is what it is used for: freight, pricing, and sizing supports with a safety factor. For a certified weight, use the mill certificate.