Steel flat bar and hex bar stock sizes: A36 hot rolled flat 1/8 to 3/8 in, 1018 hex 1/4 to 2 in and 5 to 18 mm across flats — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/steel-flat-bar-and-hex-bar-sizes/ (sheet CC BY 4.0) Basis: Continental Steel (A36 flat bar list, first 25 sizes), Online Metals (flat 3/8 x 3; 1018 hex inch and metric sizes), Metals Depot (1018 hex with lb/ft and lengths) Catalog version: 2026-10-20 Sizes: see table below - Hex bar is sized by its width across flats (AF). Distributor tables: Metals Depot (C1018 cold finished hexagon, ASTM A108, AISI 1018: 12 sizes with lb/ft; lengths 2, 4, 6, 12 ft or cut to size) and Online Metals (same grade: 16 inch sizes from 1/4 to 2 in, and 9 metric sizes 5 to 18 mm in 60 in lengths; 25 of 30 listings were visible). Weights come only from Metals Depot. A 1-5/16 in size is listed by Online Metals without an across-flats value; it is shown from its name. - Flat bar: Continental Steel's hot rolled flat bar list (A36, square edge, 20 ft lengths) has 280 sizes; only the first 25 were readable, all 1/8 in and 3/16 in thick. Rows below are those, plus Online Metals' 3/8 x 3 in (3.84 lb/ft). Continental's page has two apparent typos: 1/8 x 1 is printed 4.250 lb/ft (its own 20 ft weight, 8.50 lb, gives 0.425, which is used) and 3/16 x '1 5/8' has the decimal 1.375 and the weight of a 1-3/8 in bar, so that row is omitted. Steel weighs about 3.4 lb per foot per square inch of section, which reproduces the listed weights to rounding. - Most distributors cut flat bar to length; Online Metals states custom cuts up to 240 in. Other widths and thicknesses (1/4, 3/8, 1/2 in and up to 12 in wide) exist in the 280-size list but were not readable. - Aluminum and stainless flat bar are on their own pages (aluminum-flat-bar-and-round-bar-sizes, stainless-steel-round-and-flat-bar-sizes); round and square steel bar on bar-stock-sizes-round-square-steel-aluminum. - No files: a flat bar is a rectangle and a hex bar a prism, which a table already describes at every size and length. shape size decimal, in mm weight, lb/ft source hex 1018 cold finished 1/4 in AF 0.2500 6.35 0.20 Online Metals + Metals Depot hex 1018 cold finished 5/16 in AF 0.3125 7.94 0.30 Online Metals + Metals Depot hex 1018 cold finished 3/8 in AF 0.3750 9.52 0.42 Online Metals + Metals Depot hex 1018 cold finished 7/16 in AF 0.4375 11.11 0.60 Online Metals + Metals Depot hex 1018 cold finished 1/2 in AF 0.5000 12.70 0.74 Online Metals + Metals Depot hex 1018 cold finished 5/8 in AF 0.6250 15.88 1.15 Online Metals + Metals Depot hex 1018 cold finished 11/16 in AF 0.6875 17.46 1.39 Online Metals + Metals Depot hex 1018 cold finished 3/4 in AF 0.7500 19.05 1.66 Online Metals + Metals Depot hex 1018 cold finished 7/8 in AF 0.8750 22.22 2.25 Online Metals + Metals Depot hex 1018 cold finished 1 in AF 1.0000 25.40 2.94 Online Metals + Metals Depot hex 1018 cold finished 1-1/8 in AF 1.1250 28.57 3.75 Online Metals + Metals Depot hex 1018 cold finished 1-1/4 in AF 1.2500 31.75 — Online Metals hex 1018 cold finished 1-5/16 in AF 1.3125 33.34 — Online Metals hex 1018 cold finished 1-1/2 in AF 1.5000 38.10 — Online Metals hex 1018 cold finished 1-3/4 in AF 1.7500 44.45 — Online Metals hex 1018 cold finished 2 in AF 2.0000 50.80 12.00 Online Metals + Metals Depot hex 1018 cold finished 5 mm AF 0.1969 5 — Online Metals (60 in length) hex 1018 cold finished 6 mm AF 0.2362 6 — Online Metals (60 in length) hex 1018 cold finished 7 mm AF 0.2756 7 — Online Metals (60 in length) hex 1018 cold finished 8 mm AF 0.3150 8 — Online Metals (60 in length) hex 1018 cold finished 10 mm AF 0.3937 10 — Online Metals (60 in length) hex 1018 cold finished 12 mm AF 0.4724 12 — Online Metals (60 in length) hex 1018 cold finished 13 mm AF 0.5118 13 — Online Metals (60 in length) hex 1018 cold finished 15 mm AF 0.5906 15 — Online Metals (60 in length) hex 1018 cold finished 18 mm AF 0.7087 18 — Online Metals (60 in length) flat bar A36 hot rolled 1/8 x 1/2 in 0.1250 x 0.5000 3.17 x 12.70 0.213 Continental Steel flat bar A36 hot rolled 1/8 x 5/8 in 0.1250 x 0.6250 3.17 x 15.88 0.266 Continental Steel flat bar A36 hot rolled 1/8 x 3/4 in 0.1250 x 0.7500 3.17 x 19.05 0.319 Continental Steel flat bar A36 hot rolled 1/8 x 1 in 0.1250 x 1.0000 3.17 x 25.40 0.425 Continental Steel (page prints 4.250; its 20 ft weight gives 0.425) flat bar A36 hot rolled 1/8 x 1-1/4 in 0.1250 x 1.2500 3.17 x 31.75 0.531 Continental Steel flat bar A36 hot rolled 1/8 x 1-3/8 in 0.1250 x 1.3750 3.17 x 34.92 0.478 Continental Steel flat bar A36 hot rolled 1/8 x 1-1/2 in 0.1250 x 1.5000 3.17 x 38.10 0.638 Continental Steel flat bar A36 hot rolled 1/8 x 1-3/4 in 0.1250 x 1.7500 3.17 x 44.45 0.744 Continental Steel flat bar A36 hot rolled 1/8 x 2 in 0.1250 x 2.0000 3.17 x 50.80 0.85 Continental Steel flat bar A36 hot rolled 1/8 x 2-1/2 in 0.1250 x 2.5000 3.17 x 63.50 1.06 Continental Steel flat bar A36 hot rolled 1/8 x 3 in 0.1250 x 3.0000 3.17 x 76.20 1.28 Continental Steel flat bar A36 hot rolled 1/8 x 4 in 0.1250 x 4.0000 3.17 x 101.60 1.7 Continental Steel flat bar A36 hot rolled 1/8 x 5 in 0.1250 x 5.0000 3.17 x 127.00 2.13 Continental Steel flat bar A36 hot rolled 1/8 x 6 in 0.1250 x 6.0000 3.17 x 152.40 2.55 Continental Steel flat bar A36 hot rolled 1/8 x 7 in 0.1250 x 7.0000 3.17 x 177.80 2.98 Continental Steel flat bar A36 hot rolled 1/8 x 8 in 0.1250 x 8.0000 3.17 x 203.20 3.4 Continental Steel flat bar A36 hot rolled 1/8 x 10 in 0.1250 x 10.0000 3.17 x 254.00 4.25 Continental Steel flat bar A36 hot rolled 1/8 x 12 in 0.1250 x 12.0000 3.17 x 304.80 5.1 Continental Steel flat bar A36 hot rolled 3/16 x 1/2 in 0.1875 x 0.5000 4.76 x 12.70 0.319 Continental Steel flat bar A36 hot rolled 3/16 x 5/8 in 0.1875 x 0.6250 4.76 x 15.88 0.398 Continental Steel flat bar A36 hot rolled 3/16 x 3/4 in 0.1875 x 0.7500 4.76 x 19.05 0.478 Continental Steel flat bar A36 hot rolled 3/16 x 1 in 0.1875 x 1.0000 4.76 x 25.40 0.638 Continental Steel flat bar A36 hot rolled 3/16 x 1-1/4 in 0.1875 x 1.2500 4.76 x 31.75 0.797 Continental Steel flat bar A36 hot rolled 3/16 x 1-1/2 in 0.1875 x 1.5000 4.76 x 38.10 0.956 Continental Steel flat bar A36 hot rolled 3/8 x 3 in 0.3750 x 3.0000 9.52 x 76.20 3.84 Online Metals Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Continental Steel & Tube: Hot rolled flat bar (A36, square edge, 20 ft): first 25 of 280 listed sizes with lb/ft — web — Publisher's page; dimensions are facts — https://continentalsteel.com/viewitems/steel-bars/hot-rolled-flat-bar - Online Metals: 0.375 x 3 in A36 hot rolled flat bar: 3.84 lb per foot, custom cuts to 240 in — web — Publisher's page; dimensions are facts — https://www.onlinemetals.com/en/buy/carbon-steel/0-375-x-3-carbon-steel-rectangle-bar-a36-hot-rolled/pid/10062 - Metals Depot: C1018 cold finished hexagon (AISI 1018, ASTM A108): sizes, lb/ft, lengths — web — Publisher's page; dimensions are facts — https://www.metalsdepot.com/cold-finish-steel-products/cold-finish-steel-hexagon - Online Metals: Carbon steel hex bar 1018 cold finish (ASTM A108): inch sizes and metric 5 to 18 mm, 60 in — web — Publisher's page; dimensions are facts — https://www.onlinemetals.com/en/buy/carbon-steel-hex-bar-1018 No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. API: https://xemstudio.com/api/geometry?object=steel-flat-bar-and-hex-bar-sizes