A pipe is a hollow cylinder
All pipe weight comes from one idea: the metal is the ring between the outside and the bore, so its weight is the volume of that ring times the density of the material. Work out the metal cross-sectional area, multiply by density for the weight per unit length, then by the run length for the total:
The metal cross-sectional area is worth reporting on its own — it's what drives both the weight and the structural strength of the section — so this pipe weight calculator shows it alongside the weight per foot and per metre.
Use outside diameter and wall, not the nominal size
Weight depends on the metal actually present, and the nominal pipe size is only a label. For a given size the outside diameter is fixed while the wall thickness varies with the schedule, so the honest inputs are the real outside diameter and the wall (or, equivalently, the inside diameter). That's what the tool asks for, in either combination, rather than guessing from a nominal number. If you only have a nominal size, get the outside diameter first from the pipe size conversion calculator.
Outside diameter is constant; the wall does the work
A common surprise is that a heavier schedule doesn't change the outside diameter at all — only the wall, the bore and the weight move. A thicker wall means a smaller inside diameter and a heavier pipe at the very same outside diameter. The calculator is built around that fact: keep the outside diameter fixed and vary the wall, and you'll watch the weight climb while the outside number holds still.
The steel kg/m shortcut
For steel there's a tidy shortcut that's handy for a quick cross-check, with the wall and outside diameter both in millimetres:
For a 60.3 mm outside diameter with a 3.91 mm wall that's 0.02466 × 3.91 × (60.3 − 3.91) ≈ 5.4 kg/m, which matches the full density-based figure. The tool shows this steel shortcut next to the general result; the density method works for any material because you supply the density, while the shortcut is steel-specific because its constant bakes in the steel density.
Water-filled weight
For supports and floor loads you often want the weight of the pipe full of water, which is the metal weight plus the water sitting in the bore:
The calculator reports the empty pipe weight, the water content and the filled weight together, per unit length and for the whole run, so you can size hangers and check loads without a second tool.
Material densities
Density is the only material-specific number in the calculation, so getting it right is what makes the answer match your real material. The presets use standard published densities; you can type a custom value for an alloy or grade that isn't listed.
| Material | Density (kg/m³) |
|---|---|
| Carbon steel | 7,850 |
| Stainless steel | 8,000 |
| Copper | 8,960 |
| Brass | 8,500 |
| Aluminium | 2,700 |
| Cast iron | 7,200 |
| PVC | 1,380 |
| HDPE | 950 |
| Water (for filled weight) | 1,000 |
Spelling note for searchers: aluminium and aluminum are the same metal, and the figures are identical whether you read weight per metre or weight per foot, kg/m or lb/ft — the tool gives both at once.
Worked examples
Example 1 — two-inch steel
An NPS 2 carbon-steel pipe (OD 2.375 in) with a 0.154 in wall weighs about 3.65 lb/ft, which is roughly 5.43 kg/m. Open it with ?od=2.375&wall=0.154&mat=steel&unit=in&len=20.
Example 2 — same pipe, full of water
That pipe has a 2.067 in bore, which holds roughly 1.45 lb of water per foot, lifting the filled weight to a little over 5 lb/ft. The tool shows the empty, water and filled figures so the make-up is clear.
Pipe weight FAQ
How do I calculate the weight of a pipe?
Treat the pipe as a hollow cylinder. Work out the metal cross-sectional area as π÷4 times the outside diameter squared minus the inside diameter squared, where the inside diameter is the outside diameter minus twice the wall thickness. Multiply that area by the material density for the weight per unit length, then by the run length for the total. This tool does the full chain from your outside diameter, wall and material and reports weight per foot, per metre and for the whole run.
Why use the outside diameter and wall instead of the nominal size?
Because the nominal pipe size is a label, not a measured dimension, and weight comes from the metal actually present. For a given size the outside diameter is fixed while the wall thickness changes with the schedule — a thicker wall means a smaller bore and a heavier pipe at the same outside diameter. So the honest inputs are the real outside diameter and the wall (or the inside diameter), which this calculator asks for directly rather than guessing from a nominal label.
Does a higher schedule change the outside diameter?
No. The outside diameter stays constant for a given size across schedules; only the wall thickness, the inside diameter and therefore the weight change. A heavier schedule has a thicker wall, a smaller bore and more weight for the same outside diameter. That's exactly why this tool keeps the outside diameter fixed and lets you vary the wall: change the wall and watch the weight move while the outside diameter holds.
What is the quick formula for steel pipe weight in kg/m?
A widely used shortcut for steel is weight in kilograms per metre equals 0.02466 times the wall times the outside diameter minus the wall, with both in millimetres. For example a pipe of 60.3 mm outside diameter with a 3.91 mm wall gives 0.02466 × 3.91 × (60.3 − 3.91), about 5.4 kg/m. The tool shows this steel shortcut alongside the full density-based figure as a cross-check; the general method works for any material because you supply the density.
How do I find the weight of a pipe full of water?
Add the weight of the water in the bore to the weight of the metal. The water content per unit length is the density of water times π÷4 times the inside diameter squared, using a water density of 1000 kg per cubic metre. The calculator reports the empty pipe weight, the water content and the filled weight together, per unit length and for the whole run, so you can size supports and check loads.
What density should I use for different pipe materials?
Standard published densities in kg per cubic metre are roughly: carbon steel 7850, stainless steel 8000, copper 8960, brass 8500, aluminium 2700, cast iron 7200, PVC 1380 and HDPE 950, with water at 1000. The tool loads these as presets and lets you type a custom density for an alloy or grade not listed. Density is the only material-specific number in the calculation, so getting it right is what makes the result match your actual material.
Is this pipe weight calculator free and private?
Yes. It's free, needs no signup or download, and runs entirely in your browser, so nothing you enter leaves your device. You can copy a shareable link that reopens it with your outside diameter, wall, material, units and length already filled in, and it keeps working offline once loaded.