Round size reference
A513 round tubing sizes
A theoretical dimension and weight table for 15 common round mechanical tubing sizes. Every value is computed from nominal dimensions — planning numbers, not acceptance criteria.
Each row below is computed with the same formulas as the tube weight calculator: ID = OD − 2 × wall, area = π/4 × (OD² − ID²), and weight per foot from a nominal steel density of 0.2836 lb/in³. Click a size for its full dimensional reference, piece-weight table, and ordering checklist.
On this page
Round size table
Read the table left to right: the nominal OD and wall define the size; the ID, wall-to-OD ratio, and weight per foot are derived from them. The wall-to-OD ratio (wall ÷ OD, as a percentage) is a quick thinness indicator — lower ratios flag thin-walled sections where handling and forming behavior deserve more attention.
| Size (OD × wall) | OD (in) | Wall (in) | ID (in) | Wall/OD | Weight (lb/ft) |
|---|---|---|---|---|---|
| 3/4" OD × .049" wall | 0.750 | 0.049 | 0.652 | 6.5% | 0.367 |
| 3/4" OD × .065" wall | 0.750 | 0.065 | 0.620 | 8.7% | 0.476 |
| 3/4" OD × .083" wall | 0.750 | 0.083 | 0.584 | 11.1% | 0.592 |
| 1" OD × .065" wall | 1.000 | 0.065 | 0.870 | 6.5% | 0.650 |
| 1" OD × .083" wall | 1.000 | 0.083 | 0.834 | 8.3% | 0.814 |
| 1" OD × .120" wall | 1.000 | 0.120 | 0.760 | 12.0% | 1.129 |
| 1-1/4" OD × .065" wall | 1.250 | 0.065 | 1.120 | 5.2% | 0.824 |
| 1-1/4" OD × .083" wall | 1.250 | 0.083 | 1.084 | 6.6% | 1.036 |
| 1-1/4" OD × .120" wall | 1.250 | 0.120 | 1.010 | 9.6% | 1.450 |
| 1-1/2" OD × .083" wall | 1.500 | 0.083 | 1.334 | 5.5% | 1.257 |
| 1-1/2" OD × .120" wall | 1.500 | 0.120 | 1.260 | 8.0% | 1.771 |
| 1-1/2" OD × .156" wall | 1.500 | 0.156 | 1.188 | 10.4% | 2.242 |
| 2" OD × .083" wall | 2.000 | 0.083 | 1.834 | 4.2% | 1.701 |
| 2" OD × .120" wall | 2.000 | 0.120 | 1.760 | 6.0% | 2.412 |
| 2" OD × .188" wall | 2.000 | 0.188 | 1.624 | 9.4% | 3.642 |
How to use these values
These are dimensional planning references, not product listings: this reference makes no claim about what is stocked, produced, or available anywhere. A size becomes an order only when combined with an A513 type, grade, condition, and explicit tolerance requirements against the purchased standard.
For a size not seeded here, or for square and rectangular sections, use the tube weight calculator directly — it accepts any dimensions.