Structural steel weight is listed as mass per metre (kg/m) for every standard section, so the weight of a piece is its kg/m times its length. A W200x27 beam weighs 26.6 kg/m, an HSS 102x102x6.4 post 18.2 kg/m, a C200x17 channel 17.1 kg/m and an L102x102x9.5 angle 14.6 kg/m. Plate is worked out by area: 7.85 kg per square metre for each millimetre of thickness.
This page puts the common sizes of every main shape in one chart, in metric with imperial equivalents. For a full list of any single shape, follow the links to our shape-by-shape charts.
How to use this chart
- Weight of a member = kg/m x length in metres. A 4.5 m W250x33 weighs 32.9 x 4.5 = 148 kg.
- Imperial: kg/m x 0.672 = lb/ft. lb/ft x 1.488 = kg/m.
- Sizes are actual, not nominal. The depth in a W name is a family name; the chart gives real depths.
- Sources. W-shape and HSS values are from the CISC section tables. S, HP, channel, angle, pipe and round HSS values are from the AISC Shapes Database metric listing. Rounding can make the last digit differ slightly between tables.
- This is a selection, not the full range. Hundreds of sections exist, and availability varies. For design properties, engineers use the CISC Handbook of Steel Construction.
The method for shapes that aren't in a table, and allowances for plates and bolts, are covered in how to calculate the weight of structural steel.
W-shapes: beams and columns
| Metric | Imperial | Depth (mm) | Flange width (mm) | kg/m | lb/ft |
|---|---|---|---|---|---|
| W100x19 | W4x13 | 106 | 103 | 19.4 | 13 |
| W150x22 | W6x15 | 152 | 152 | 22.5 | 15 |
| W150x30 | W6x20 | 157 | 153 | 29.8 | 20 |
| W200x27 | W8x18 | 207 | 133 | 26.6 | 18 |
| W200x31 | W8x21 | 210 | 134 | 31.2 | 21 |
| W200x46 | W8x31 | 203 | 203 | 46.2 | 31 |
| W250x33 | W10x22 | 258 | 146 | 32.9 | 22 |
| W250x39 | W10x26 | 262 | 147 | 38.5 | 26 |
| W250x49 | W10x33 | 247 | 202 | 49.1 | 33 |
| W310x39 | W12x26 | 310 | 165 | 38.8 | 26 |
| W310x52 | W12x35 | 317 | 167 | 52.2 | 35 |
| W310x60 | W12x40 | 303 | 203 | 59.7 | 40 |
| W360x45 | W14x30 | 352 | 171 | 44.8 | 30 |
| W360x57 | W14x38 | 358 | 172 | 56.8 | 38 |
| W410x54 | W16x36 | 403 | 177 | 53.7 | 36 |
| W460x60 | W18x40 | 455 | 153 | 59.7 | 40 |
| W530x74 | W21x50 | 529 | 166 | 74.4 | 50 |
| W610x82 | W24x55 | 599 | 178 | 82.4 | 55 |
More W sizes, with web and flange thicknesses, are in our Canadian W-shape chart.
S, HP, channels and angles
Standard I-beams (S) and bearing piles (HP):
| Metric | Imperial | Depth (mm) | Flange width (mm) | kg/m | lb/ft |
|---|---|---|---|---|---|
| S200x27 | S8x18.4 | 203 | 102 | 27.4 | 18.4 |
| S310x47 | S12x31.8 | 305 | 127 | 47.3 | 31.8 |
| HP200x53 | HP8x36 | 204 | 207 | 53.0 | 36 |
| HP310x79 | HP12x53 | 300 | 305 | 79.0 | 53 |
Channels (C):
| Metric | Imperial | Depth (mm) | Flange width (mm) | kg/m | lb/ft |
|---|---|---|---|---|---|
| C75x6 | C3x4.1 | 76 | 35.8 | 6.1 | 4.1 |
| C100x8 | C4x5.4 | 102 | 40.1 | 8.0 | 5.4 |
| C150x12 | C6x8.2 | 152 | 48.8 | 12.2 | 8.2 |
| C200x17 | C8x11.5 | 203 | 57.4 | 17.1 | 11.5 |
| C250x23 | C10x15.3 | 254 | 66.0 | 22.8 | 15.3 |
| C310x31 | C12x20.7 | 305 | 74.7 | 30.8 | 20.7 |
| C380x50 | C15x33.9 | 381 | 86.4 | 50.4 | 33.9 |
The full channel list is in our C-channel weight per metre chart.
Angles (L), legs and thickness in mm:
| Metric | Imperial (in) | kg/m | lb/ft |
|---|---|---|---|
| L51x51x6.4 | 2 x 2 x 1/4 | 4.7 | 3.19 |
| L76x76x6.4 | 3 x 3 x 1/4 | 7.3 | 4.9 |
| L89x89x6.4 | 3-1/2 x 3-1/2 x 1/4 | 8.6 | 5.8 |
| L102x102x6.4 | 4 x 4 x 1/4 | 9.8 | 6.6 |
| L102x102x9.5 | 4 x 4 x 3/8 | 14.6 | 9.8 |
| L127x89x7.9 | 5 x 3-1/2 x 5/16 | 12.9 | 8.7 |
| L152x102x9.5 | 6 x 4 x 3/8 | 18.2 | 12.3 |
| L152x152x9.5 | 6 x 6 x 3/8 | 22.2 | 14.9 |
HSS and pipe
HSS is named by outside size and wall thickness, so the weight never appears in the name. These are some of the most-asked-about sizes.
Square and rectangular HSS:
| Section (mm) | Imperial (in) | kg/m | lb/ft |
|---|---|---|---|
| HSS 51x51x4.8 | 2 x 2 x 3/16 | 6.4 | 4.3 |
| HSS 76x76x4.8 | 3 x 3 x 3/16 | 10.3 | 6.9 |
| HSS 76x76x6.4 | 3 x 3 x 1/4 | 13.1 | 8.8 |
| HSS 89x89x6.4 | 3-1/2 x 3-1/2 x 1/4 | 15.6 | 10.5 |
| HSS 102x102x6.4 | 4 x 4 x 1/4 | 18.2 | 12.2 |
| HSS 127x127x6.4 | 5 x 5 x 1/4 | 23.2 | 15.6 |
| HSS 152x152x6.4 | 6 x 6 x 1/4 | 28.3 | 19.0 |
| HSS 152x152x9.5 | 6 x 6 x 3/8 | 40.9 | 27.5 |
| HSS 203x203x6.4 | 8 x 8 x 1/4 | 38.5 | 25.9 |
| HSS 102x51x4.8 | 4 x 2 x 3/16 | 10.3 | 6.9 |
| HSS 152x102x6.4 | 6 x 4 x 1/4 | 23.2 | 15.6 |
| HSS 203x102x6.4 | 8 x 4 x 1/4 | 28.3 | 19.0 |
| HSS 254x152x6.4 | 10 x 6 x 1/4 | 38.5 | 25.9 |
| HSS 305x203x9.5 | 12 x 8 x 3/8 | 71.4 | 48.0 |
Round HSS and pipe:
| Section | Outside diameter | kg/m | lb/ft |
|---|---|---|---|
| Round HSS, 6.4 mm wall | 88.9 mm (3.5 in) | 12.9 | 8.7 |
| Round HSS, 4.8 mm wall | 114.3 mm (4.5 in) | 12.9 | 8.7 |
| Round HSS, 6.4 mm wall | 168.3 mm (6.625 in) | 25.4 | 17.1 |
| Round HSS, 6.4 mm wall | 219.1 mm (8.625 in) | 33.3 | 22.4 |
| Pipe, NPS 3 standard weight | 88.9 mm (3.5 in) | 11.3 | 7.6 |
| Pipe, NPS 3-1/2 standard weight | 101.6 mm (4.0 in) | 13.6 | 9.1 |
| Pipe, NPS 4 standard weight | 114.3 mm (4.5 in) | 16.1 | 10.8 |
More HSS sizes are in our HSS weight per metre chart.
Plate and flat bar
Plate weight depends only on thickness. Multiply the kg/m² by the plate's area in square metres.
| Thickness | kg/m² | Imperial equivalent |
|---|---|---|
| 6 mm | 47.1 | 1/4 in plate (6.35 mm): 49.8 kg/m², about 10.2 lb/ft² |
| 8 mm | 62.8 | |
| 10 mm | 78.5 | 3/8 in plate (9.5 mm): 74.8 kg/m² |
| 12 mm | 94.2 | 1/2 in plate (12.7 mm): 99.7 kg/m² |
| 16 mm | 125.6 | |
| 20 mm | 157.0 | 3/4 in plate (19.1 mm): 149.5 kg/m² |
| 25 mm | 196.3 | 1 in plate (25.4 mm): 199.4 kg/m² |
Flat bar works the same way per metre of length: thickness (mm) x width (mm) x 0.00785 = kg/m. A 10 x 100 mm flat bar weighs 7.85 kg/m.
Example: a 250 x 250 mm base plate, 12 mm thick, is 0.0625 m² x 94.2 = about 5.9 kg before holes.
Using the chart for a quick take-off
Here is a typical basement job worked from the chart:
| Piece | Calculation | Weight |
|---|---|---|
| 1 beam, W250x33, 6.0 m | 32.9 x 6.0 | 197 kg |
| 2 posts, HSS 89x89x6.4, 2.4 m each | 15.6 x 2.4 x 2 | 75 kg |
| 4 plates, 150 x 150 x 10 mm | 0.0225 x 78.5 x 4 | 7 kg |
| Total | about 279 kg |
Weights like this tell you how many people or what equipment it takes to move a beam into a house, what a trailer is carrying, and roughly how a supplier builds a quote, since structural steel is largely bought and fabricated by weight. Fabrication, connections, finishing and delivery all add to the cost, so weight alone doesn't give you a price.
If you're not sure which shape you're looking at, our guide to the types of structural steel shapes explains each one.
Get a take-off from your drawings
Weights from a chart are a good first estimate. For a real number, we prepare a free take-off from your structural drawings, listing every piece, its length and weight, and then quote supply, fabrication and, if you need it, installation. Send your drawings, or browse the beams, posts, plates and channels on our steel products page.
Frequently asked questions
How do you find the weight of a structural steel member?
Look up its mass per metre in a section table, then multiply by the length. A W250x33 weighs 32.9 kg/m, so a 6 m beam weighs about 197 kg before plates and connections.
How much does structural steel weigh per cubic metre?
Steel weighs about 7,850 kg per cubic metre. That is why steel plate weighs 7.85 kg per square metre for every millimetre of thickness.
What does kg/m mean in a steel size?
It is the mass of one metre of the section. For W, S, HP and C shapes the second number in the name is that mass, rounded: a W200x27 weighs 26.6 kg/m. HSS and angle names give dimensions instead, so you need a table.
How do I convert kg/m to lb/ft?
Multiply kg/m by 0.672. To go the other way, multiply lb/ft by 1.488. A W8x18 at 18 lb/ft is 26.8 kg/m by straight conversion; the Canadian table lists it at 26.6 kg/m.
