FL sections
and their properties

A flat bar (FL) is a hot rolled bar of rectangular cross-section defined by EN 10058. It is designated by width and thickness, for example FL 40×6.

Find by requirements Compare sections

Profile	bmm▲	tmm▲	Acm²▲	I_ycm⁴▲	I_zcm⁴▲	W_el,ycm³▲	W_pl,ycm³▲	Gkg/m▲
FL 10×5	10	5	0.5	0.04	0.01	0.08	0.13	0.39
FL 12×5	12	5	0.6	0.07	0.01	0.12	0.18	0.47
FL 12×6	12	6	0.72	0.09	0.02	0.14	0.22	0.57
FL 15×5	15	5	0.75	0.14	0.02	0.19	0.28	0.59
FL 15×6	15	6	0.9	0.17	0.03	0.23	0.34	0.71
FL 15×8	15	8	1.2	0.23	0.06	0.3	0.45	0.94
FL 15×10	15	10	1.5	0.28	0.13	0.38	0.56	1.18
FL 16×5	16	5	0.8	0.17	0.02	0.21	0.32	0.63
FL 16×6	16	6	0.96	0.2	0.03	0.26	0.38	0.75
FL 16×8	16	8	1.28	0.27	0.07	0.34	0.51	1
FL 16×10	16	10	1.6	0.34	0.13	0.43	0.64	1.26
FL 20×4	20	4	0.8	0.27	0.01	0.27	0.4	0.63
FL 20×5	20	5	1	0.33	0.02	0.33	0.5	0.78
FL 20×6	20	6	1.2	0.4	0.04	0.4	0.6	0.94
FL 20×8	20	8	1.6	0.53	0.09	0.53	0.8	1.26
FL 20×10	20	10	2	0.67	0.17	0.67	1	1.57
FL 20×12	20	12	2.4	0.8	0.29	0.8	1.2	1.88
FL 20×15	20	15	3	1	0.56	1	1.5	2.35
FL 25×4	25	4	1	0.52	0.01	0.42	0.63	0.78
FL 25×5	25	5	1.25	0.65	0.03	0.52	0.78	0.98
FL 25×6	25	6	1.5	0.78	0.04	0.63	0.94	1.18
FL 25×8	25	8	2	1.04	0.11	0.83	1.25	1.57
FL 25×10	25	10	2.5	1.3	0.21	1.04	1.56	1.96
FL 25×12	25	12	3	1.56	0.36	1.25	1.88	2.35
FL 25×15	25	15	3.75	1.95	0.7	1.56	2.34	2.94
FL 30×4	30	4	1.2	0.9	0.02	0.6	0.9	0.94
FL 30×5	30	5	1.5	1.13	0.03	0.75	1.13	1.18
FL 30×6	30	6	1.8	1.35	0.05	0.9	1.35	1.41
FL 30×8	30	8	2.4	1.8	0.13	1.2	1.8	1.88
FL 30×10	30	10	3	2.25	0.25	1.5	2.25	2.35
FL 30×12	30	12	3.6	2.7	0.43	1.8	2.7	2.83
FL 30×15	30	15	4.5	3.38	0.84	2.25	3.38	3.53
FL 30×20	30	20	6	4.5	2	3	4.5	4.71
FL 35×4	35	4	1.4	1.43	0.02	0.82	1.23	1.1
FL 35×5	35	5	1.75	1.79	0.04	1.02	1.53	1.37
FL 35×6	35	6	2.1	2.14	0.06	1.23	1.84	1.65
FL 35×8	35	8	2.8	2.86	0.15	1.63	2.45	2.2
FL 35×10	35	10	3.5	3.57	0.29	2.04	3.06	2.75
FL 35×12	35	12	4.2	4.29	0.5	2.45	3.67	3.3
FL 35×15	35	15	5.25	5.36	0.98	3.06	4.59	4.12
FL 35×20	35	20	7	7.15	2.33	4.08	6.13	5.49
FL 40×4	40	4	1.6	2.13	0.02	1.07	1.6	1.26
FL 40×5	40	5	2	2.67	0.04	1.33	2	1.57
FL 40×6	40	6	2.4	3.2	0.07	1.6	2.4	1.88
FL 40×8	40	8	3.2	4.27	0.17	2.13	3.2	2.51
FL 40×10	40	10	4	5.33	0.33	2.67	4	3.14
FL 40×12	40	12	4.8	6.4	0.58	3.2	4.8	3.77
FL 40×15	40	15	6	8	1.13	4	6	4.71
FL 40×20	40	20	8	10.67	2.67	5.33	8	6.28
FL 40×25	40	25	10	13.33	5.21	6.67	10	7.85
FL 40×30	40	30	12	16	9	8	12	9.42
FL 45×4	45	4	1.8	3.04	0.02	1.35	2.02	1.41
FL 45×5	45	5	2.25	3.8	0.05	1.69	2.53	1.77
FL 45×6	45	6	2.7	4.56	0.08	2.02	3.04	2.12
FL 45×8	45	8	3.6	6.08	0.19	2.7	4.05	2.83
FL 45×10	45	10	4.5	7.59	0.38	3.38	5.06	3.53
FL 45×12	45	12	5.4	9.11	0.65	4.05	6.08	4.24
FL 45×15	45	15	6.75	11.39	1.27	5.06	7.59	5.3
FL 45×20	45	20	9	15.19	3	6.75	10.13	7.06
FL 45×25	45	25	11.25	18.98	5.86	8.44	12.66	8.83
FL 45×30	45	30	13.5	22.78	10.13	10.13	15.19	10.6
FL 50×4	50	4	2	4.17	0.03	1.67	2.5	1.57
FL 50×5	50	5	2.5	5.21	0.05	2.08	3.13	1.96
FL 50×6	50	6	3	6.25	0.09	2.5	3.75	2.35
FL 50×8	50	8	4	8.33	0.21	3.33	5	3.14
FL 50×10	50	10	5	10.42	0.42	4.17	6.25	3.92
FL 50×12	50	12	6	12.5	0.72	5	7.5	4.71
FL 50×15	50	15	7.5	15.63	1.41	6.25	9.38	5.89
FL 50×20	50	20	10	20.83	3.33	8.33	12.5	7.85
FL 50×25	50	25	12.5	26.04	6.51	10.42	15.63	9.81
FL 50×30	50	30	15	31.25	11.25	12.5	18.75	11.77
FL 60×5	60	5	3	9	0.06	3	4.5	2.35
FL 60×6	60	6	3.6	10.8	0.11	3.6	5.4	2.83
FL 60×8	60	8	4.8	14.4	0.26	4.8	7.2	3.77
FL 60×10	60	10	6	18	0.5	6	9	4.71
FL 60×12	60	12	7.2	21.6	0.86	7.2	10.8	5.65
FL 60×15	60	15	9	27	1.69	9	13.5	7.06
FL 60×20	60	20	12	36	4	12	18	9.42
FL 60×25	60	25	15	45	7.81	15	22.5	11.77
FL 60×30	60	30	18	54	13.5	18	27	14.13
FL 60×35	60	35	21	63	21.44	21	31.5	16.48
FL 60×40	60	40	24	72	32	24	36	18.84
FL 70×5	70	5	3.5	14.29	0.07	4.08	6.13	2.75
FL 70×6	70	6	4.2	17.15	0.13	4.9	7.35	3.3
FL 70×8	70	8	5.6	22.87	0.3	6.53	9.8	4.4
FL 70×10	70	10	7	28.58	0.58	8.17	12.25	5.49
FL 70×12	70	12	8.4	34.3	1.01	9.8	14.7	6.59
FL 70×15	70	15	10.5	42.88	1.97	12.25	18.38	8.24
FL 70×20	70	20	14	57.17	4.67	16.33	24.5	10.99
FL 70×25	70	25	17.5	71.46	9.11	20.42	30.63	13.74
FL 70×30	70	30	21	85.75	15.75	24.5	36.75	16.48
FL 70×35	70	35	24.5	100.04	25.01	28.58	42.88	19.23
FL 70×40	70	40	28	114.33	37.33	32.67	49	21.98
FL 80×5	80	5	4	21.33	0.08	5.33	8	3.14
FL 80×6	80	6	4.8	25.6	0.14	6.4	9.6	3.77
FL 80×8	80	8	6.4	34.13	0.34	8.53	12.8	5.02
FL 80×10	80	10	8	42.67	0.67	10.67	16	6.28
FL 80×12	80	12	9.6	51.2	1.15	12.8	19.2	7.54
FL 80×15	80	15	12	64	2.25	16	24	9.42
FL 80×20	80	20	16	85.33	5.33	21.33	32	12.56
FL 80×25	80	25	20	106.67	10.42	26.67	40	15.7
FL 80×30	80	30	24	128	18	32	48	18.84
FL 80×35	80	35	28	149.33	28.58	37.33	56	21.98
FL 80×40	80	40	32	170.67	42.67	42.67	64	25.12
FL 80×50	80	50	40	213.33	83.33	53.33	80	31.4
FL 80×60	80	60	48	256	144	64	96	37.68
FL 90×5	90	5	4.5	30.38	0.09	6.75	10.13	3.53
FL 90×6	90	6	5.4	36.45	0.16	8.1	12.15	4.24
FL 90×8	90	8	7.2	48.6	0.38	10.8	16.2	5.65
FL 90×10	90	10	9	60.75	0.75	13.5	20.25	7.06
FL 90×12	90	12	10.8	72.9	1.3	16.2	24.3	8.48
FL 90×15	90	15	13.5	91.13	2.53	20.25	30.38	10.6
FL 90×20	90	20	18	121.5	6	27	40.5	14.13
FL 90×25	90	25	22.5	151.88	11.72	33.75	50.63	17.66
FL 90×30	90	30	27	182.25	20.25	40.5	60.75	21.19
FL 90×35	90	35	31.5	212.63	32.16	47.25	70.88	24.73
FL 90×40	90	40	36	243	48	54	81	28.26
FL 90×50	90	50	45	303.75	93.75	67.5	101.25	35.32
FL 90×60	90	60	54	364.5	162	81	121.5	42.39
FL 100×5	100	5	5	41.67	0.1	8.33	12.5	3.92
FL 100×6	100	6	6	50	0.18	10	15	4.71
FL 100×8	100	8	8	66.67	0.43	13.33	20	6.28
FL 100×10	100	10	10	83.33	0.83	16.67	25	7.85
FL 100×12	100	12	12	100	1.44	20	30	9.42
FL 100×15	100	15	15	125	2.81	25	37.5	11.77
FL 100×20	100	20	20	166.67	6.67	33.33	50	15.7
FL 100×25	100	25	25	208.33	13.02	41.67	62.5	19.62
FL 100×30	100	30	30	250	22.5	50	75	23.55
FL 100×35	100	35	35	291.67	35.73	58.33	87.5	27.47
FL 100×40	100	40	40	333.33	53.33	66.67	100	31.4
FL 100×50	100	50	50	416.67	104.17	83.33	125	39.25
FL 100×60	100	60	60	500	180	100	150	47.1
FL 120×6	120	6	7.2	86.4	0.22	14.4	21.6	5.65
FL 120×8	120	8	9.6	115.2	0.51	19.2	28.8	7.54
FL 120×10	120	10	12	144	1	24	36	9.42
FL 120×12	120	12	14.4	172.8	1.73	28.8	43.2	11.3
FL 120×15	120	15	18	216	3.38	36	54	14.13
FL 120×20	120	20	24	288	8	48	72	18.84
FL 120×25	120	25	30	360	15.63	60	90	23.55
FL 120×30	120	30	36	432	27	72	108	28.26
FL 120×35	120	35	42	504	42.88	84	126	32.97
FL 120×40	120	40	48	576	64	96	144	37.68
FL 120×50	120	50	60	720	125	120	180	47.1
FL 120×60	120	60	72	864	216	144	216	56.52
FL 130×8	130	8	10.4	146.47	0.55	22.53	33.8	8.16
FL 130×10	130	10	13	183.08	1.08	28.17	42.25	10.2
FL 130×12	130	12	15.6	219.7	1.87	33.8	50.7	12.25
FL 130×15	130	15	19.5	274.63	3.66	42.25	63.38	15.31
FL 130×20	130	20	26	366.17	8.67	56.33	84.5	20.41
FL 130×25	130	25	32.5	457.71	16.93	70.42	105.63	25.51
FL 130×30	130	30	39	549.25	29.25	84.5	126.75	30.61
FL 130×35	130	35	45.5	640.79	46.45	98.58	147.88	35.72
FL 130×40	130	40	52	732.33	69.33	112.67	169	40.82
FL 130×50	130	50	65	915.42	135.42	140.83	211.25	51.02
FL 130×60	130	60	78	1 098.5	234	169	253.5	61.23
FL 140×8	140	8	11.2	182.93	0.6	26.13	39.2	8.79
FL 140×10	140	10	14	228.67	1.17	32.67	49	10.99
FL 140×12	140	12	16.8	274.4	2.02	39.2	58.8	13.19
FL 140×15	140	15	21	343	3.94	49	73.5	16.48
FL 140×20	140	20	28	457.33	9.33	65.33	98	21.98
FL 140×25	140	25	35	571.67	18.23	81.67	122.5	27.47
FL 140×30	140	30	42	686	31.5	98	147	32.97
FL 140×35	140	35	49	800.33	50.02	114.33	171.5	38.46
FL 140×40	140	40	56	914.67	74.67	130.67	196	43.96
FL 140×50	140	50	70	1 143.33	145.83	163.33	245	54.95
FL 140×60	140	60	84	1 372	252	196	294	65.94
FL 150×6	150	6	9	168.75	0.27	22.5	33.75	7.06
FL 150×8	150	8	12	225	0.64	30	45	9.42
FL 150×10	150	10	15	281.25	1.25	37.5	56.25	11.77
FL 150×12	150	12	18	337.5	2.16	45	67.5	14.13
FL 150×15	150	15	22.5	421.88	4.22	56.25	84.38	17.66
FL 150×20	150	20	30	562.5	10	75	112.5	23.55
FL 150×25	150	25	37.5	703.13	19.53	93.75	140.63	29.44
FL 150×30	150	30	45	843.75	33.75	112.5	168.75	35.32
FL 150×35	150	35	52.5	984.38	53.59	131.25	196.88	41.21
FL 150×40	150	40	60	1 125	80	150	225	47.1
FL 150×50	150	50	75	1 406.25	156.25	187.5	281.25	58.87
FL 150×60	150	60	90	1 687.5	270	225	337.5	70.65
FL 150×80	150	80	120	2 250	640	300	450	94.2
FL 160×8	160	8	12.8	273.07	0.68	34.13	51.2	10.05
FL 160×10	160	10	16	341.33	1.33	42.67	64	12.56
FL 160×12	160	12	19.2	409.6	2.3	51.2	76.8	15.07
FL 160×15	160	15	24	512	4.5	64	96	18.84
FL 160×20	160	20	32	682.67	10.67	85.33	128	25.12
FL 160×25	160	25	40	853.33	20.83	106.67	160	31.4
FL 160×30	160	30	48	1 024	36	128	192	37.68
FL 160×35	160	35	56	1 194.67	57.17	149.33	224	43.96
FL 160×40	160	40	64	1 365.33	85.33	170.67	256	50.24
FL 160×50	160	50	80	1 706.67	166.67	213.33	320	62.8
FL 160×60	160	60	96	2 048	288	256	384	75.36
FL 170×8	170	8	13.6	327.53	0.73	38.53	57.8	10.68
FL 170×10	170	10	17	409.42	1.42	48.17	72.25	13.34
FL 170×12	170	12	20.4	491.3	2.45	57.8	86.7	16.01
FL 170×15	170	15	25.5	614.13	4.78	72.25	108.38	20.02
FL 170×20	170	20	34	818.83	11.33	96.33	144.5	26.69
FL 170×25	170	25	42.5	1 023.54	22.14	120.42	180.63	33.36
FL 170×30	170	30	51	1 228.25	38.25	144.5	216.75	40.03
FL 170×35	170	35	59.5	1 432.96	60.74	168.58	252.88	46.71
FL 170×40	170	40	68	1 637.67	90.67	192.67	289	53.38
FL 170×50	170	50	85	2 047.08	177.08	240.83	361.25	66.72
FL 170×60	170	60	102	2 456.5	306	289	433.5	80.07
FL 180×8	180	8	14.4	388.8	0.77	43.2	64.8	11.3
FL 180×10	180	10	18	486	1.5	54	81	14.13
FL 180×12	180	12	21.6	583.2	2.59	64.8	97.2	16.96
FL 180×15	180	15	27	729	5.06	81	121.5	21.19
FL 180×20	180	20	36	972	12	108	162	28.26
FL 180×25	180	25	45	1 215	23.44	135	202.5	35.32
FL 200×8	200	8	16	533.33	0.85	53.33	80	12.56
FL 200×10	200	10	20	666.67	1.67	66.67	100	15.7
FL 200×12	200	12	24	800	2.88	80	120	18.84
FL 200×15	200	15	30	1 000	5.63	100	150	23.55
FL 200×20	200	20	40	1 333.33	13.33	133.33	200	31.4
FL 200×25	200	25	50	1 666.67	26.04	166.67	250	39.25

About FL profiles

A flat bar (FL) is a hot rolled bar of rectangular cross-section defined by EN 10058. It is designated by width and thickness, for example FL 40×6.

Typical uses are gusset plates, stiffeners, splice plates, anchor parts, railings and general fabrication. Rectangle properties follow exact closed-form formulas, so the tabulated values are computed exactly rather than rounded catalogue figures.

The table covers the preferred sizes of EN 10058:2018: flat bars 10 to 150 mm wide and wide flats 160 to 200 mm, in thicknesses from 4 to 80 mm.

Frequently Asked Questions

How are flat bars designated?

By width and thickness in millimetres, for example FL 40×6 or simply 40×6. Spellings like 40x6 or 40*6 are common and the site search accepts them.

Which standard defines flat bars?

Dimensions and tolerances of hot rolled flat bars are given by EN 10058, with material per EN 10025.

Which axis of a flat bar is the strong one?

Axis y in our table means bending on edge, using the full width of the bar. Bending flat is far less stiff, see the Iz column.