Timing belt profiles: GT2, HTD 3M / 5M / 8M, T5, T10, AT5, MXL, XL, L, H: pitch, tooth height and pulley pitch diameter — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/timing-belt-profiles-pitch-and-tooth/ (sheet CC BY 4.0) Basis: Texas Belting pitch chart for pitch and tooth height, optibelt ISO 5296 numbers for XL / L / H, York Industries for MXL / XL / L pitch; pitch diameter computed as N × pitch / π Catalog version: 2026-10-20 Sizes: see table below - Pitch is the distance between belt tooth centres along the pitch line; a pulley with N teeth has pitch Ø = N × pitch / π (a definition, so the last three columns are computed: 20 teeth of 2 mm pitch is 12.73 mm; 20 teeth of 5 mm is 31.83 mm). The pulley's outside diameter is the pitch Ø minus twice the pitch-line differential of the profile; the differentials (for example GT2's 0.254 mm, already on the gt2-pulleys page) were not readable in any table reached for the other profiles, so no OD column is given. - Table sources: pitch and tooth height of all thirteen profiles come from Texas Belting's pitch chart (a distributor; belt thickness is printed there only for HTD 3M / 5M / 8M). XL, L and H are ISO 5296 profiles and optibelt prints the standard numbers: overall belt thickness hs (2.3, 3.6, 4.0), tooth height ht (1.27, 1.91, 2.29), tooth angle 2β (50°, 40°, 40°), tooth width s (2.57, 4.65, 6.12) and foot / head radii (0.38, 0.51, 1.02). York Industries confirms the MXL, XL and L pitches (0.080, 0.200, 0.375 in). - Disagreement: H profile tooth height is 2.54 mm (0.100 in) at Texas Belting and 2.29 mm at optibelt; both are shown. XL and L agree (1.27 / 1.91). MXL 2.032 mm is 0.080 in. Other profiles: tooth heights for T2.5, T5, AT5, T10, AT10, GT2 and HTD have one source only. - Same pitch does not mean same belt: T5 and HTD 5M are both 5 mm pitch but their tooth heights are 1.2 and 2.1 mm, and 2 mm (GT2), 2.5 mm (T2.5) and 3 mm (HTD 3M) belts are listed as separate profiles. ISO 5296 covers the MXL, XL, L, H, XH and XXH profiles (optibelt). - No tooth-profile files: only XL, L and H have a tooth angle / width / radii here, and the pulley groove (not the belt tooth) is what a drawing needs, which no table read gave. GT2 pulleys with an approximate tooth form are on the gt2-pulleys page and are labelled approximate there. - Not tabulated: pitch-line differentials, minimum teeth, belt widths per profile (Texas Belting lists a width range per profile), width codes (e.g. 025 = 1/4 in for XL) and pulley flange sizes. Gates / SDP-SI / Misumi / optibelt publish them; none was readable here. profile pitch, mm pitch, in tooth height, mm belt thickness, mm tooth angle 2β (ISO 5296) tooth width s, mm foot / head radius, mm pitch Ø of 20 teeth, mm pitch Ø of 30 teeth, mm pitch Ø of 40 teeth, mm MXL 2.032 0.08 0.51 — — — — 12.94 19.40 25.87 GT2 (2 mm) 2 0.0787 0.75 — — — — 12.73 19.10 25.46 T2.5 2.5 0.0984 0.7 — — — — 15.92 23.87 31.83 HTD 3M 3 0.1181 1.2 2.4 — — — 19.10 28.65 38.20 T5 5 0.1969 1.2 — — — — 31.83 47.75 63.66 HTD 5M 5 0.1969 2.1 3.8 — — — 31.83 47.75 63.66 AT5 5 0.1969 1.2 — — — — 31.83 47.75 63.66 XL 5.08 0.2 1.27 2.3 (optibelt) 50° 2.57 0.38 / 0.38 32.34 48.51 64.68 HTD 8M 8 0.315 3.4 5.6 — — — 50.93 76.39 101.86 L 9.525 0.375 1.91 3.6 (optibelt) 40° 4.65 0.51 / 0.51 60.64 90.96 121.28 T10 10 0.3937 2.5 — — — — 63.66 95.49 127.32 AT10 10 0.3937 2.5 — — — — 63.66 95.49 127.32 H 12.7 0.5 2.54 (optibelt 2.29) 4 (optibelt) 40° 6.12 1.02 / 1.02 80.85 121.28 161.70 Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Texas Belting: Timing belt pitch chart: pitch and tooth height for MXL, GT2, T2.5, 3M, T5, 5M, AT5, XL, 8M, L, T10, AT10, H, 14M, XH, XXH — web — Publisher's page; dimensions are facts — https://texasbelting.com/pages/timing-belt-pitch-chart - optibelt: ZR rubber timing belt drives technical data (ISO 5296): XL / L / H pitch, thickness hs, tooth height ht, tooth angle 2β, tooth width s, radii — web — Publisher's page; dimensions are facts — https://cdn.shopify.com/s/files/1/0667/2885/3800/files/Optibelt-ZR_Rubber-Timing-Belt-Drives_teknisk_data.pdf - York Industries: Synchronous drive specifications: MXL 0.080 in, XL 0.200 in, L 0.375 in pitch — web — Publisher's page; dimensions are facts — https://www.york-ind.com/engineering/timing-pulleys-tensioners-pulley-stock-and-flanges/synchronous-drive-specifications.html 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=timing-belt-profiles-pitch-and-tooth