What is steel beam load tables in structural steel design?

Steel Beam Load Tables is a key concept in structural steel engineering governed by international design standards including AISC 360, EN 1993, AS 4100, and CSA S16. This reference page provides definitions, formulas, values, and worked examples.

How do you calculate steel beam load tables?

The calculation method depends on the governing design code and loading condition. Refer to the formulas and worked examples on this page. For automated calculation, use the free tools linked in the calculator CTA section below.

Where can I find official steel beam load tables values and tables?

Official values are published in the AISC Steel Construction Manual (US), EN 1993 standards (Europe), AS 4100 (Australia), and CSA S16 (Canada). The AISC Shapes Database v16.0 provides tabulated values for all standard sections. This reference page summarizes commonly used values for quick lookup.

Steel Beam Load Tables — W-Shape Allowable Uniform Load by Span

Steel beam load tables are the most-used reference in structural engineering offices. Instead of running a full calculation for every beam, engineers look up the allowable uniform load for a given span and section. This reference provides allowable uniform load tables for common W-shapes, explains how the values are calculated, and shows how to select the lightest adequate section for any span and load condition.

How to use these tables

What the tables show

Each table lists the factored uniform load capacity (phi*wn, in kips per foot) for W-shapes at specific spans. The capacity is the lesser of:

Flexural capacity: phi*Mn/L^2 x 8 (moment-limited)
Shear capacity: phi*Vn/L x 2 (shear-limited, rarely controls for uniform loads)
Deflection capacity: w that produces delta = L/360 (live load deflection limit)

The tables show all three capacities and the governing limit state.

Load table conventions

Steel grade: ASTM A992 (Fy = 50 ksi, Fu = 65 ksi)
Design method: LRFD (AISC 360-22)
phi (flexure) = 0.90, phi (shear) = 1.00
Lateral bracing: Continuous (composite deck, Lb = 0)
Deflection limit: L/360 for live load, L/240 for total load
Support condition: Simply supported

W-shape uniform load tables

W8 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W8x10	10	30.3	2.42	14.3	1.20	L/360	1.20
W8x10	15	30.3	1.08	9.55	0.36	L/360	0.36
W8x10	20	30.3	0.61	7.16	0.15	L/360	0.15
W8x18	10	62.5	5.00	22.8	2.01	L/360	2.01
W8x18	15	62.5	2.22	15.2	0.59	L/360	0.59
W8x18	20	62.5	1.25	11.4	0.25	L/360	0.25
W8x18	25	62.5	0.80	9.12	0.13	L/360	0.13
W8x31	10	115	9.20	49.9	3.56	L/360	3.56
W8x31	15	115	4.09	33.3	1.06	L/360	1.06
W8x31	20	115	2.30	25.0	0.44	L/360	0.44
W8x31	25	115	1.47	20.0	0.23	L/360	0.23

W10 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W10x12	10	43.0	3.44	14.6	1.56	L/360	1.56
W10x12	15	43.0	1.53	9.73	0.46	L/360	0.46
W10x12	20	43.0	0.86	7.30	0.19	L/360	0.19
W10x30	10	137	10.96	40.4	3.79	L/360	3.79
W10x30	15	137	4.88	26.9	1.12	L/360	1.12
W10x30	20	137	2.74	20.2	0.47	L/360	0.47
W10x30	25	137	1.76	16.2	0.24	L/360	0.24

W12 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W12x14	10	68.8	5.50	14.0	2.35	L/360	2.35
W12x14	15	68.8	2.45	9.33	0.70	L/360	0.70
W12x14	20	68.8	1.38	7.00	0.29	L/360	0.29
W12x26	15	154	5.47	21.6	1.34	L/360	1.34
W12x26	20	154	3.08	16.2	0.56	L/360	0.56
W12x26	25	154	1.97	13.0	0.29	L/360	0.29
W12x40	15	234	8.32	34.2	1.82	L/360	1.82
W12x40	20	234	4.68	25.6	0.77	L/360	0.77
W12x40	25	234	3.00	20.5	0.39	L/360	0.39
W12x40	30	234	2.08	17.1	0.23	L/360	0.23
W12x50	20	298	5.96	34.0	1.01	L/360	1.01
W12x50	25	298	3.81	27.2	0.52	L/360	0.52
W12x50	30	298	2.65	22.7	0.30	L/360	0.30

W14 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W14x22	15	152	5.40	18.4	1.30	L/360	1.30
W14x22	20	152	3.04	13.8	0.55	L/360	0.55
W14x22	25	152	1.95	11.0	0.28	L/360	0.28
W14x30	15	220	7.82	28.2	1.72	L/360	1.72
W14x30	20	220	4.40	21.2	0.73	L/360	0.73
W14x30	25	220	2.82	16.9	0.37	L/360	0.37
W14x30	30	220	1.96	14.1	0.21	L/360	0.21

W16 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W16x26	15	226	8.04	19.3	1.85	L/360	1.85
W16x26	20	226	4.52	14.5	0.78	L/360	0.78
W16x26	25	226	2.90	11.6	0.40	L/360	0.40
W16x31	20	282	5.64	22.8	0.96	L/360	0.96
W16x31	25	282	3.61	18.3	0.49	L/360	0.49
W16x31	30	282	2.51	15.2	0.28	L/360	0.28
W16x40	20	389	7.78	31.8	1.31	L/360	1.31
W16x40	25	389	4.99	25.4	0.67	L/360	0.67
W16x40	30	389	3.46	21.2	0.39	L/360	0.39

W18 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W18x35	20	249	4.98	28.4	1.06	L/360	1.06
W18x35	25	249	3.18	22.7	0.54	L/360	0.54
W18x35	30	249	2.21	18.9	0.31	L/360	0.31
W18x40	20	294	5.88	36.3	1.27	L/360	1.27
W18x40	25	294	3.76	29.1	0.65	L/360	0.65
W18x40	30	294	2.61	24.2	0.38	L/360	0.38
W18x46	25	341	4.37	38.9	0.82	L/360	0.82
W18x46	30	341	3.03	32.4	0.47	L/360	0.47
W18x46	35	341	2.23	27.8	0.30	L/360	0.30

W21 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W21x44	20	358	7.16	34.0	1.75	L/360	1.75
W21x44	25	358	4.58	27.2	0.90	L/360	0.90
W21x44	30	358	3.18	22.7	0.52	L/360	0.52
W21x44	35	358	2.34	19.4	0.33	L/360	0.33
W21x50	25	413	5.29	37.2	1.04	L/360	1.04
W21x50	30	413	3.67	31.0	0.60	L/360	0.60
W21x50	35	413	2.70	26.6	0.38	L/360	0.38
W21x57	30	475	4.22	43.1	0.72	L/360	0.72
W21x57	35	475	3.10	36.9	0.45	L/360	0.45
W21x57	40	475	2.37	32.3	0.30	L/360	0.30

W24 shapes

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W24x55	25	452	5.79	38.8	1.20	L/360	1.20
W24x55	30	452	4.02	32.3	0.69	L/360	0.69
W24x55	35	452	2.96	27.7	0.44	L/360	0.44
W24x62	30	514	4.57	40.1	0.82	L/360	0.82
W24x62	35	514	3.36	34.4	0.52	L/360	0.52
W24x62	40	514	2.57	30.1	0.35	L/360	0.35
W24x68	30	611	5.43	47.0	0.94	L/360	0.94
W24x68	35	611	3.99	40.3	0.60	L/360	0.60
W24x68	40	611	3.06	35.3	0.40	L/360	0.40
W24x76	35	700	4.57	52.1	0.70	L/360	0.70
W24x76	40	700	3.50	45.6	0.47	L/360	0.47

W27 and W30 shapes (long-span)

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W27x84	30	858	7.63	59.0	1.22	L/360	1.22
W27x84	35	858	5.61	50.6	0.77	L/360	0.77
W27x84	40	858	4.29	44.3	0.52	L/360	0.52
W30x90	35	1,090	7.12	65.3	1.01	L/360	1.01
W30x90	40	1,090	5.45	57.2	0.68	L/360	0.68
W30x90	45	1,090	4.31	50.8	0.47	L/360	0.47
W30x99	40	1,200	6.00	72.8	0.78	L/360	0.78
W30x99	45	1,200	4.74	64.7	0.55	L/360	0.55
W30x108	40	1,340	6.70	82.1	0.88	L/360	0.88
W30x108	45	1,340	5.29	72.9	0.62	L/360	0.62
W30x124	45	1,610	6.36	98.1	0.74	L/360	0.74
W30x124	50	1,610	5.15	88.3	0.54	L/360	0.54

W33 and W36 shapes (girders)

Section	Span (ft)	phi*Mn (kip-ft)	Flex Capacity (k/ft)	Shear Cap (k/ft)	L/360 LL Cap (k/ft)	Governs	Max w_u (k/ft)
W33x118	40	1,780	8.90	89.7	1.06	L/360	1.06
W33x118	45	1,780	7.03	79.7	0.75	L/360	0.75
W33x118	50	1,780	5.70	71.7	0.54	L/360	0.54
W33x130	45	2,020	7.98	105	0.84	L/360	0.84
W33x130	50	2,020	6.46	94.7	0.61	L/360	0.61
W36x135	45	2,350	9.29	108	0.94	L/360	0.94
W36x135	50	2,350	7.52	97.4	0.69	L/360	0.69
W36x150	50	2,720	8.70	127	0.82	L/360	0.82
W36x150	55	2,720	7.19	115	0.61	L/360	0.61

Key insight: deflection governs almost always

In every table above, L/360 live load deflection governs the capacity. This is the single most important insight from these tables: for non-composite floor beams at typical office loads, deflection controls the design, not strength.

When does strength govern instead?

Condition	Governing Limit	Typical Scenario
Short spans (< 10 ft)	Shear	Heavily loaded transfer beams
Heavy point loads	Moment	Crane beams, transfer girders
Seismic/wind frames	Moment	Moment frame beams
Composite beams	Moment	Shear studs engage the slab

For typical gravity floor beams (uniform load, 15-40 ft spans), deflection governs.

How to calculate these values

Flexural capacity

phi x M_n = phi x F_y x Z_x / 12  (for compact sections with Lb < Lp)
w_max = 8 x phi x M_n / L^2

Shear capacity

phi x V_n = phi x 0.60 x F_y x d x t_w  (for unstiffened webs)
w_max = 2 x phi x V_n / L

Live load deflection capacity (L/360)

delta_max = L x 12 / 360 = L/30 in
delta = 5 x w_L x (Lx12)^4 / (384 x E x I)
w_L_max = delta_max x 384 x E x I / (5 x (Lx12)^4)

Quick beam selection guide

For 30 ft span, 10 ft spacing, 50 psf office live load

Factored load: w_u = 1.2 x 70psf x 10ft/1000 + 1.6 x 50psf x 10ft/1000 = 0.84 + 0.80 = 1.64 kip/ft

From the W21 table: W21x44 at 30 ft carries 0.52 k/ft. Not enough without composite action.

Solution: Use composite action with shear studs. A W21x44 composite with studs has effective I of 1,200+ in^4, tripling the deflection capacity. This is why most 30+ ft floor beams are designed compositely.

Cross-code comparison for beam load tables

Parameter	AISC 360-22	AS 4100:2020	EN 1993-1-1	CSA S16:19
Method	LRFD (phi=0.9)	LRFD (phi=0.9)	LRFD (gamma_M)	LRFD (phi=0.9)
Deflection limit (floor)	L/360	Span/360	L/300	L/360
Deflection limit (roof)	L/240	Span/250	L/200	L/240
E (steel)	29,000 ksi	200,000 MPa	210,000 MPa	200,000 MPa

Common mistakes using load tables

Using ASD values from old tables with LRFD loads. Pre-2005 AISC manuals used ASD (allowable stress) values. These tables use LRFD. Mixing them overestimates capacity by 30-50%.
Ignoring the deflection-governed capacity. The moment capacity looks generous (5-10 k/ft) but the deflection capacity is often 5-10x less. Always use the deflection-limited value for floor beams.
Not accounting for unbraced length. These tables assume Lb = 0 (continuous bracing from deck). For beams without deck bracing, the moment capacity drops significantly due to lateral-torsional buckling.
Applying uniform load tables to point loads. A point load at midspan produces the same maximum moment as a uniform load of 2P/L. But the shear diagram is different.
Using the wrong steel grade. A36 (Fy = 36 ksi) and A992 (Fy = 50 ksi) differ by 28% in moment capacity. Modern W-shapes are A992.
Forgetting connection weight. Add 10% to the beam weight for connection material (clip angles, end plates, bolts).

Frequently asked questions

What is the lightest W-shape for a 25 ft span at 1.5 k/ft factored load? W16x40 carries 0.67 k/ft (deflection governed). W18x46 carries 0.82. W21x50 carries 1.04. W24x55 carries 1.20. None carry 1.5 k/ft without composite action. Use composite design or a W24x76.

Do these tables work for roof beams? Yes, but change the deflection limit from L/360 to L/240. This roughly doubles the allowable load from the deflection column.

What about composite beams? Composite beams with shear studs have 1.5-2.5x the effective I of the bare steel section. A W21x44 composite at 30 ft can carry 1.5+ k/ft vs 0.52 non-composite.

Can I use these for continuous beams? Not directly. Continuous beams carry 20-30% more uniform load than simply supported. Use the continuous beam calculator for multi-span conditions.

Run this calculation

Related references

Disclaimer

This page is for educational and reference use only. It does not constitute professional engineering advice. All design values must be verified against the applicable standard and project specification before use. The site operator disclaims liability for any loss arising from this information.

Design Resources

Calculator tools

Design guides