How do I convert section properties to metric?

Multiply inches by 25.4 for millimeters, in² by 645 for mm², in⁴ by 416,231 for mm⁴, in³ by 16,387 for mm³, and lb/ft by 1.488 for kg/m. Each section page also includes pre-computed metric values.

AISC Steel Section Properties Database

Q: How many AISC sections are in the database?

1,660 sections covering W, M, S, HP, C, MC, L, WT, MT, ST, HSS rectangular, HSS round, and Pipe shapes from the AISC Shapes Database v16.0.

Q: What is the largest W-shape?

W44×408 — depth 44.8 inches, weight 408 lb/ft, Ix = 38,700 in⁴, Sx = 1,730 in³, Zx = 2,000 in³.

Q: What does HSS mean?

Hollow Structural Section. Available in rectangular, square, and round profiles, cold-formed or ERW welded.

Browse 1,660 steel sections from the AISC Shapes Database v16.0 — covering W, M, S, HP, C, MC, L, WT, MT, ST, HSS rectangular, HSS round, and Pipe shapes. Each page includes full dimensions, section properties, torsional properties, and metric conversions.

This is a hub page (directory) for all AISC section types. Use the links below to view full section properties for any shape.

What you'll find here

Complete dimensions (depth, flange width, web thickness, flange thickness)
Cross-sectional area, weight per foot, and moment of inertia
Elastic and plastic section modulus (Sx, Zx)
Radius of gyration (rx, ry)
Torsional properties (J, Cw)
Metric (SI) conversions for all properties
Links to 1,660 individual section pages

Shape types

W-Shapes (Wide Flange)

289 sections from W4×13 to W44×408. The most common beam and column shape for building construction. Weight range: 10–408 lb/ft, depth range: 4–44.8 in. Used for beams, columns, moment frames, and composite members.

M-Shapes (Miscellaneous)

16 sections that do not meet W-shape flange width criteria. Used for specialized or lighter applications. Weight: 4–10.3 lb/ft, depth: 4–10 in.

M10×8

S-Shapes (Standard I-Beams)

28 I-beams with sloped inner flange surfaces (1:6 taper). The original hot-rolled beam profile. Weight: 5.5–42.9 lb/ft, depth: 3–24 in.

S24×100

HP-Shapes (Bearing Piles)

22 sections with equal depth and flange width for foundation piles. Weight: 36–204 lb/ft, depth: 8–18 in.

HP14×117

C-Shapes (Standard Channels)

32 channel sections with sloped inner flange surfaces. Used for light framing, girts, purlins, and bracing. Weight: 3.5–50 lb/ft, depth: 3–15 in.

C15×50

MC-Shapes (Miscellaneous Channels)

40 channel sections that do not meet C-shape criteria. Weight: 4.6–51.9 lb/ft, depth: 3–18 in.

MC12×50

L-Shapes (Angles)

137 equal-leg and unequal-leg angles. The most versatile shape for bracing, trusses, and connections. Weight: 1.7–40.6 lb/ft, leg length: 0.5–8 in.

L8×8×1⅛

WT-Shapes (Structural Tees)

289 T-sections cut from W-shapes. Used for truss chords, stiffeners, and hangers. Weight: 5.5–200 lb/ft, depth: 3–22 in.

WT22×200

MT-Shapes (Miscellaneous Tees)

14 T-sections cut from M-shapes. Weight: 2–5.2 lb/ft, depth: 2–5 in.

MT5×5.2

ST-Shapes (Standard Tees)

28 T-sections cut from S-shapes. Weight: 2.7–21.5 lb/ft, depth: 2–12 in.

ST12×21.5

HSS — Rectangular and Square

525 cold-formed or ERW hollow structural sections. Excellent torsional resistance and compression capacity. Weight: 2.3–150.4 lb/ft, width: 1–20 in.

HSS — Round

189 round hollow structural sections. Ideal for bracing, columns, and exposed steel. Weight: 2.1–136 lb/ft, OD: 1.66–14 in.

HSS14.000×0.750

Pipe (Round)

51 standard-weight and extra-strong steel pipe sections (ASTM A53 Grade B). Weight: 6.1–333.3 lb/ft, NPS: 1.32–24 in.

Pipe 20 Sch 40

How to use section properties

Section properties determine the strength and stiffness of steel members. Here is how each property is used in design:

Area (A): Used for axial tension and compression checks, and for gross section yielding. Measured in in² or mm².

Moment of Inertia (Ix, Iy): Resistance to bending about each axis. Larger I means stiffer beam, smaller deflection. Measured in in⁴ or mm⁴.

Section Modulus (Sx, Sy): Elastic bending capacity: My = Fy × S. Used for yielding checks. Measured in in³ or mm³.

Plastic Modulus (Zx, Zy): Plastic bending capacity: Mp = Fy × Z. Used for compact section strength. Measured in in³ or mm³.

Radius of Gyration (rx, ry): Used for slenderness and buckling calculations: KL/r. Measured in in or mm.

Torsional Constant (J): Saint-Venant torsional stiffness. Measured in in⁴ or mm⁴.

Warping Constant (Cw): Warping torsional stiffness for open sections (W, S, C shapes). Measured in in⁶ or mm⁶.

Quick design checks using section properties

Beam flexural capacity (compact section): φbMp = φb × Fy × Zx / 12 (kip-ft)

Column axial capacity (elastic buckling): Pe = π² × E × I / (KL)²

Tension member yielding: φtPn = φt × Fy × Ag

Shear area: Aw = d × tw (for W-shapes, approximately)

Design code applicability

Section properties are independent of design code — the same shape has the same dimensions whether you are using AISC 360, AS 4100, EN 1993, or CSA S16. However, the design checks that USE these properties differ between codes:

AISC 360-22 (US): Uses φ factors (tension 0.90, shear 0.90, flexure 0.90, compression 0.90). Compactness limits per Table B4.1b.
AS 4100-2020 (Australia): Uses capacity factor φ (0.9 for sections). Slenderness limits per AS 4100 Table 5.1.
EN 1993-1-1 (Europe): Uses partial factors γM0 (1.00), γM1 (1.00). Section classification per EN 1993-1-1 Table 5.2.
CSA S16-19 (Canada): Uses resistance factor φ (0.90). Class limits per CSA S16 Clause 11.

How section properties are measured

All dimensions and properties follow the AISC Shapes Database v16.0 standard:

d: Nominal depth — the overall depth of the section (inches)
bf: Flange width — width of each flange (inches)
tf: Flange thickness — thickness of the flange (inches)
tw: Web thickness — thickness of the web (inches)
kdes: Distance from outer face of flange to toe of web fillet (design value)
kdet: Same as kdes but detailing value (may differ slightly)
WT: For ST, MT, WT shapes — the stem thickness equals the original W-shape flange thickness
HSS: Outside dimensions are nominal. Corner radii are accounted for in property calculations per AISC specification.

Data provenance

Section properties are sourced from the AISC Shapes Database v16.0 (published 2022). The database is the authoritative source of section property data for structural steel design in the United States and is referenced by AISC 360 and the AISC Steel Construction Manual.

Dimensions and properties for HSS sections follow the AISC Hollow Structural Sections (HSS) database, which aligns with ASTM A500 (round and rectangular) and ASTM A1085 (improved ductility) specifications.

Pipe section properties are based on standard-weight (STD/Schedule 40) and extra-strong (XS/Schedule 80) pipe sizes per ASME B36.10, with material properties per ASTM A53 Grade B.

Conversion to metric (SI)

All section properties include metric equivalents on their individual pages. Conversions use these factors:

Length (in → mm): multiply by 25.4
Area (in² → mm²): multiply by 645.16
Moment of inertia (in⁴ → mm⁴): multiply by 416,231
Section modulus (in³ → mm³): multiply by 16,387
Weight (lb/ft → kg/m): multiply by 1.488

Frequently Asked Questions

How many AISC sections are there? The AISC Shapes Database v16.0 contains 1,660 sections total, covering 13 shape types.

What is the largest W-shape? W44×408 is the largest standard W-shape at 44.8-inch depth and 408 lb/ft.

What is the most common W-shape for beams? W21×50, W18×35, and W16×31 are commonly used beam sections. W21×50 balances depth, weight, and capacity for typical bay sizes.

What is the most common W-shape for columns? W14×90, W14×74, and W10×49 are common column sections. W14 shapes are preferred for columns because their depth provides good strong-axis stiffness while maintaining a practical footprint.

What does HSS stand for? Hollow Structural Section. HSS shapes are available in rectangular, square, and round profiles, formed by cold-forming or ERW (electric resistance welding).

What steel grade is standard for W-shapes? ASTM A992 (Fy = 50 ksi, Fu = 65 ksi) is the default grade for W-shapes per AISC 360.

What steel grade is used for HSS? ASTM A500 Grade C (Fy = 50 ksi round, 46 ksi rectangular) or ASTM A1085 (Fy = 50 ksi) for improved ductility.

What steel grade is used for Pipe sections? ASTM A53 Grade B (Fy = 35 ksi, Fu = 60 ksi) is standard for structural pipe.

Are metric equivalents shown? Yes, every section page includes complete metric (SI) conversions alongside US customary units.

Can I use these section properties for international codes? Yes. Section properties are geometry-based and independent of design code. The same W21×50 dimensions apply whether you design per AISC 360 (US), AS 4100 (Australia), EN 1993 (Europe), or CSA S16 (Canada). Only the phi/resistance factors and compactness limits differ.

Disclaimer (educational use only)

This page and all linked section property pages are provided for general technical information and educational use only. They do not constitute professional engineering advice, a design service, or a substitute for an independent review by a qualified structural engineer.

All real-world structural design depends on project-specific factors: actual loads, load combinations, connection details, stability systems, local building codes, and construction tolerances. You are responsible for verifying all section properties against official AISC publications or your supplier's mill certificates, validating your design with an independent method, and obtaining professional sign-off from a licensed Professional Engineer (PE) or Structural Engineer (SE).

The site operator provides the content "as is" without warranties of any kind and disclaims liability for any loss or damage arising from use of this page or any linked tools.