Interactive Structural Engineering Reference

I Beam Size Chart

Look up selected AISC wide-flange beam dimensions and section properties, switch between U.S. and SI units, inspect a dimension-driven cross-section, and compare selected shapes.

Basis: AISC Shapes Database v16.0
Coverage: 51 selected W4–W24 shapes
Units: U.S. customary and SI
Use: dimensional reference only

JavaScript enables unit switching, the live dimension diagram, filtering, sorting, copying, and comparison. The complete U.S.-unit reference table remains available below.

Selected-section dimensions

Interactive I-Beam Size Diagram

The designation is nominal. Use the displayed d, b_f, t_w, and t_f values for actual reference dimensions.

Example: W8×24 means a W shape in the nominal 8-inch depth series weighing 24 lb/ft; its actual reference depth is 7.93 in.

Dimension-driven schematic for the selected W shape. Web and flange thicknesses may be visually exaggerated for legibility; use the labeled values for engineering reference.

Selected designationW8×24Parallel-flange AISC W shape

Weight, W: 24 lb/ft
Area, A: 7.08 in²
Overall depth, d: 7.93 in
Flange width, b_f: 6.50 in
Web thickness, t_w: 0.245 in
Flange thickness, t_f: 0.400 in
Strong-axis inertia, I_x: 82.8 in⁴
Section modulus, S_x: 20.9 in³
Weak-axis radius, r_y: 1.61 in

What “I beam” means here

This interactive table focuses on selected AISC W shapes because wide-flange sections dominate modern structural-beam searches. American Standard S shapes have tapered inner flange surfaces, while miscellaneous M shapes cover sections that do not fit the regular W or S series.

Selected AISC I-Beam Size Chart (W Shapes)

Find a beam: search or sort the table, click a row to display its dimensions, and use the checkbox to compare up to four shapes.

Selected AISC W-shape dimensions and geometric properties. U.S. values are the reference values; SI values are rounded engineering conversions for display. This table does not determine beam capacity.
Select		Weight and area		Cross-section dimensions				Strong-axis properties			Action
Select											Action
	W4×13	13 lb/ft	3.83 in²	4.16 in	4.06 in	0.28 in	0.345 in	11.3 in⁴	5.46 in³	1 in
	W6×9	9 lb/ft	2.68 in²	5.9 in	3.94 in	0.17 in	0.215 in	16.4 in⁴	5.56 in³	0.905 in
	W6×12	12 lb/ft	3.55 in²	6.03 in	4 in	0.23 in	0.28 in	22.1 in⁴	7.31 in³	0.918 in
	W6×15	15 lb/ft	4.43 in²	5.99 in	5.99 in	0.23 in	0.26 in	29.1 in⁴	9.72 in³	1.46 in
	W6×20	20 lb/ft	5.87 in²	6.2 in	6.02 in	0.26 in	0.365 in	41.4 in⁴	13.4 in³	1.5 in
	W6×25	25 lb/ft	7.34 in²	6.38 in	6.08 in	0.32 in	0.455 in	53.4 in⁴	16.7 in³	1.52 in
	W8×10	10 lb/ft	2.96 in²	7.89 in	3.94 in	0.17 in	0.205 in	30.8 in⁴	7.81 in³	0.841 in
	W8×15	15 lb/ft	4.44 in²	8.11 in	4.02 in	0.245 in	0.315 in	48 in⁴	11.8 in³	0.876 in
	W8×18	18 lb/ft	5.26 in²	8.14 in	5.25 in	0.23 in	0.33 in	61.9 in⁴	15.2 in³	1.23 in
	W8×21	21 lb/ft	6.16 in²	8.28 in	5.27 in	0.25 in	0.4 in	75.3 in⁴	18.2 in³	1.26 in
	W8×24	24 lb/ft	7.08 in²	7.93 in	6.5 in	0.245 in	0.4 in	82.8 in⁴	20.9 in³	1.61 in
	W8×31	31 lb/ft	9.13 in²	8 in	7.995 in	0.285 in	0.435 in	110 in⁴	27.5 in³	2.02 in
	W8×35	35 lb/ft	10.3 in²	8.12 in	8.02 in	0.31 in	0.495 in	127 in⁴	31.2 in³	2.03 in
	W8×40	40 lb/ft	11.7 in²	8.25 in	8.07 in	0.36 in	0.56 in	146 in⁴	35.5 in³	2.04 in
	W10×12	12 lb/ft	3.54 in²	9.87 in	3.96 in	0.19 in	0.21 in	53.8 in⁴	10.9 in³	0.785 in
	W10×15	15 lb/ft	4.41 in²	9.99 in	4 in	0.23 in	0.27 in	68.9 in⁴	13.8 in³	0.81 in
	W10×19	19 lb/ft	5.62 in²	10.24 in	4.02 in	0.25 in	0.395 in	96.3 in⁴	18.8 in³	0.874 in
	W10×22	22 lb/ft	6.49 in²	10.17 in	5.75 in	0.24 in	0.36 in	118 in⁴	23.2 in³	1.33 in
	W10×26	26 lb/ft	7.61 in²	10.33 in	5.77 in	0.26 in	0.44 in	144 in⁴	27.9 in³	1.36 in
	W10×30	30 lb/ft	8.84 in²	10.47 in	5.81 in	0.3 in	0.51 in	170 in⁴	32.4 in³	1.37 in
	W12×14	14 lb/ft	4.16 in²	11.91 in	3.97 in	0.2 in	0.225 in	88.6 in⁴	14.9 in³	0.753 in
	W12×16	16 lb/ft	4.71 in²	11.99 in	3.99 in	0.22 in	0.265 in	103 in⁴	17.1 in³	0.773 in
	W12×19	19 lb/ft	5.57 in²	12.16 in	4.01 in	0.235 in	0.35 in	130 in⁴	21.3 in³	0.822 in
	W12×22	22 lb/ft	6.48 in²	12.31 in	4.03 in	0.26 in	0.425 in	156 in⁴	25.4 in³	0.848 in
	W12×26	26 lb/ft	7.65 in²	12.22 in	6.49 in	0.23 in	0.38 in	204 in⁴	33.4 in³	1.51 in
	W12×30	30 lb/ft	8.79 in²	12.34 in	6.52 in	0.26 in	0.44 in	238 in⁴	38.6 in³	1.52 in
	W12×35	35 lb/ft	10.3 in²	12.5 in	6.56 in	0.3 in	0.52 in	285 in⁴	45.6 in³	1.54 in
	W12×40	40 lb/ft	11.7 in²	11.94 in	8.005 in	0.295 in	0.515 in	307 in⁴	51.5 in³	1.94 in
	W12×50	50 lb/ft	14.6 in²	12.19 in	8.08 in	0.37 in	0.64 in	391 in⁴	64.2 in³	1.96 in
	W14×22	22 lb/ft	6.49 in²	13.74 in	5 in	0.23 in	0.335 in	199 in⁴	29 in³	1.04 in
	W14×26	26 lb/ft	7.69 in²	13.91 in	5.025 in	0.255 in	0.42 in	245 in⁴	35.3 in³	1.08 in
	W14×30	30 lb/ft	8.85 in²	13.84 in	6.73 in	0.27 in	0.385 in	291 in⁴	42 in³	1.49 in
	W14×34	34 lb/ft	10 in²	13.98 in	6.745 in	0.285 in	0.455 in	340 in⁴	48.6 in³	1.53 in
	W14×38	38 lb/ft	11.2 in²	14.1 in	6.77 in	0.31 in	0.515 in	385 in⁴	54.6 in³	1.55 in
	W14×43	43 lb/ft	12.6 in²	13.66 in	7.995 in	0.305 in	0.53 in	428 in⁴	62.7 in³	1.89 in
	W14×53	53 lb/ft	15.6 in²	13.92 in	8.06 in	0.37 in	0.66 in	541 in⁴	77.8 in³	1.92 in
	W16×26	26 lb/ft	7.68 in²	15.69 in	5.5 in	0.25 in	0.345 in	301 in⁴	38.4 in³	1.12 in
	W16×31	31 lb/ft	9.13 in²	15.88 in	5.525 in	0.275 in	0.44 in	375 in⁴	47.2 in³	1.17 in
	W16×36	36 lb/ft	10.6 in²	15.86 in	6.985 in	0.295 in	0.43 in	448 in⁴	56.5 in³	1.52 in
	W16×40	40 lb/ft	11.8 in²	16.01 in	6.995 in	0.305 in	0.505 in	518 in⁴	64.7 in³	1.57 in
	W18×35	35 lb/ft	10.3 in²	17.7 in	6 in	0.3 in	0.425 in	510 in⁴	57.6 in³	1.22 in
	W18×40	40 lb/ft	11.8 in²	17.9 in	6.015 in	0.315 in	0.525 in	612 in⁴	68.4 in³	1.27 in
	W18×46	46 lb/ft	13.5 in²	18.06 in	6.06 in	0.36 in	0.605 in	712 in⁴	78.8 in³	1.29 in
	W18×50	50 lb/ft	14.7 in²	17.99 in	7.495 in	0.355 in	0.57 in	800 in⁴	88.9 in³	1.65 in
	W18×60	60 lb/ft	17.6 in²	18.24 in	7.555 in	0.415 in	0.695 in	984 in⁴	108 in³	1.69 in
	W21×44	44 lb/ft	13 in²	20.66 in	6.5 in	0.35 in	0.45 in	843 in⁴	81.6 in³	1.26 in
	W21×50	50 lb/ft	14.7 in²	20.83 in	6.53 in	0.38 in	0.535 in	984 in⁴	94.5 in³	1.3 in
	W21×62	62 lb/ft	18.3 in²	20.99 in	8.24 in	0.4 in	0.615 in	1,330 in⁴	127 in³	1.77 in
	W24×55	55 lb/ft	16.2 in²	23.57 in	7.005 in	0.395 in	0.505 in	1,350 in⁴	114 in³	1.34 in
	W24×62	62 lb/ft	18.2 in²	23.74 in	7.04 in	0.43 in	0.59 in	1,550 in⁴	131 in³	1.38 in
	W24×76	76 lb/ft	22.4 in²	23.92 in	8.99 in	0.44 in	0.68 in	2,100 in⁴	176 in³	1.92 in

Scope: This is a selected common-shape reference, not the complete AISC shape database. Confirm the current official database, mill availability, material grade, tolerances, and project requirements before design or procurement.

Table actions and data limitations

Full-dataset and CSV downloads are intentionally unavailable. AISC publications and compiled shape data are rights-sensitive; obtain the complete current database from AISC.

Selected-shape comparison

Strong-Axis Moment of Inertia Comparison

Use table checkboxes to compare up to four discrete W shapes. Bars are used because standard designations are categories, not a continuous size scale.

Select up to four W shapes in the table to compare their strong-axis moment of inertia.

Key Takeaways

Read the designation as nominal: W8×24 does not mean the beam is exactly 8 inches deep.
Separate shape families: W shapes have parallel flange surfaces; S shapes use tapered inner flange surfaces.
Match the property to the task: I_x relates to strong-axis stiffness, while S_x is used in elastic bending-stress relationships.
Do not infer capacity: a section-property row is only one input to structural design.

I-Beam Dimensions Are Not Beam Capacity

Reference only—not member selection

This chart does not determine a safe beam size, span, or allowable load. Structural design must address material grade, load combinations, support conditions, unbraced length, local and lateral-torsional buckling, shear, deflection, vibration, holes, connections, fire protection, corrosion, applicable codes, and actual product availability.

Designation, dimensions, and properties

How to Read and Use the I-Beam Size Chart

Start with the designation, verify the actual dimensions, and then use only the section property relevant to the next engineering calculation.

How to Read W8×24

W identifies an AISC wide-flange shape. The first number is the nominal depth series in inches, and the second is the nominal weight in pounds per foot. The designation is a convenient name rather than a complete dimensional definition. In this chart, W8×24 has an actual depth d of 7.93 in, flange width b_f of 6.50 in, web thickness t_w of 0.245 in, and flange thickness t_f of 0.400 in.

W: Nominal weight per unit length: lb/ft in the U.S. designation and kg/m in the SI display.

A: Gross cross-sectional area.

d: Actual overall section depth.

b_f: Actual flange width.

t_w: Published web thickness.

t_f: Published flange thickness.

I_x: Strong-axis second moment of area, used in stiffness and deflection relationships.

S_x: Strong-axis elastic section modulus, used in the elastic bending relation f_b = M/S_x.

r_y: Weak-axis radius of gyration, a geometric quantity used in slenderness and stability calculations.

W Beams vs. S Beams vs. M Beams

W shapes

Wide-flange shapes have approximately parallel inner and outer flange surfaces. They are the default family in this interactive chart.

S shapes

American Standard beams have tapered inner flange surfaces and different detailing geometry. Do not substitute an S designation for a W designation by nominal depth alone.

M shapes

Miscellaneous shapes are standardized I-shaped sections that do not fit the regular W or S series. Use the official database for their complete properties.

Recommended Lookup Workflow

Search the exact designation when it is known, allowing either “×” or “x.”
Confirm the actual depth and flange width instead of relying on the nominal series name.
Check web and flange thicknesses when clearances, connections, coping, or detailing are involved.
Select the required property—for example, I_x for an elastic-deflection calculation or S_x for an elastic bending-stress relationship.
Continue to a design calculation that includes loading, supports, material, stability, serviceability, and applicable code provisions.

Worked Lookup Example: Comparing W8×24 and W10×30

Geometry check

W8×24: d = 7.93 in and b_f = 6.50 in.

W10×30: d = 10.47 in and b_f = 5.81 in.

The deeper designation is not necessarily wider. Check both dimensions when envelope or connection clearances matter.

Stiffness-property check

W8×24: I_x = 82.8 in⁴.

W10×30: I_x = 170 in⁴.

The W10×30 has about 2.05 times the tabulated strong-axis inertia, but that comparison alone does not establish strength, deflection compliance, or suitability.

U.S. and SI Values

The table stores one canonical U.S.-unit value for each published row. The SI interface converts from those values using fixed dimensional conversion factors, so repeated unit switching does not accumulate rounding error. Nominal designations such as W8×24 remain unchanged because they are names, not measured dimensions.

I-Beam Chart Sources, Version, and Data Scope

Selected AISC W shapes · U.S. source values with live SI conversions · Reference dataset version 1.0

This page presents a limited educational selection of frequently referenced W shapes. It does not reproduce the complete AISC database, and it intentionally provides no bulk-data download.

AISC Shapes Database v16.0Controls the standardized shape designations, dimensions, and geometric-property basis used for the reference rows.
ANSI/AISC 360-22, Specification for Structural Steel BuildingsSupports the distinction between geometric-property lookup and structural member design.
AISC Copyright PermissionsSupports the page’s limited-excerpt approach and the decision not to offer a complete database or CSV export.

Dataset and Review Details

Edition or revision: AISC Shapes Database v16.0; consistent with the 16th Edition Steel Construction Manual
Scope: 51 selected W4 through W24 wide-flange shapes
Reference units: lb/ft, in², in, in³, and in⁴
SI method: Rounded engineering conversion from canonical U.S. values; no cumulative conversion
Known exclusions: Complete W catalog, S/M/HP/WT families, design strengths, tolerances, availability, and connection properties
Last reviewed: August 2, 2026
Reviewer: Turn2Engineering Editorial Team
Rights status: Limited educational excerpt; complete-dataset redistribution and CSV disabled
Dataset version: Selected AISC W-Shape Reference 1.0

Frequently Asked Questions

What does W8×24 mean?

W identifies a wide-flange shape, 8 is the nominal depth series in inches, and 24 is the nominal weight in pounds per foot. The exact depth, flange width, and thicknesses must be read from the property row.

Is a W beam the same as an I beam?

A W shape has an I-shaped cross-section and is often called an I beam in general usage, but its flanges are approximately parallel. An American Standard S beam has tapered inner flange surfaces and is a distinct standardized family.

Why is actual beam depth different from the nominal size?

The designation groups shapes into nominal depth series; it is not an exact dimensional callout. Rolled shapes within the same nominal series can have different actual depths as flange and web proportions change.

Can this chart tell me what beam size I need?

No. Safe member selection requires project loads, supports, span, unbraced length, steel grade, stability, serviceability, connections, applicable codes, and other design conditions that a dimension chart does not evaluate.

What are Ix, Sx, and ry?

I_x is the strong-axis second moment of area, S_x is the strong-axis elastic section modulus, and r_y is the weak-axis radius of gyration used in slenderness and stability relationships.

I Beam Size Chart Summary

Use the diagram and table to identify a standardized W-shape designation, verify its actual cross-section dimensions, and copy the geometric property needed for a separate engineering calculation. Keep the unit system consistent and treat every nominal designation as a name rather than an exact dimension.

After the lookup, continue with the governing structural analysis and design checks. The lightest, deepest, or highest-inertia row is not automatically the correct member for a project.

Where to Go Next

Continue to the Beam Calculator
Evaluate a separate beam-analysis case using the actual loading and support conditions.
Review the Bending Stress Formula
See how bending moment and section modulus relate in elastic stress calculations.