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Parallel Pin Dimensions (ISO 2338 / DIN 7, 0.6 to 50 mm)
Guide · Updated October 28, 2026
ISO 2338 covers unhardened parallel pins (it replaced DIN 7), 0.6 to 50 mm. The chamfer values agree in the ISO 2338:1997 preview (iTeh), the Boltport and fasten.it ISO 2338 tables and the Daniel-Gruppe DIN 7 / ISO 2338 sheet. Check your supplier for critical work.
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Step by step
- Pick the diameter: d, 0.6 to 50 mm; this is the hole size.
- Pick the tolerance class: m6 for a press fit in an H7 hole, h8 for a looser locating fit.
- Read the chamfer: c is the approximate end chamfer for that diameter.
- Check length tolerance: ±0.25 mm for 2 to 10 mm long, ±0.5 mm for 12 to 50 mm, ±0.75 mm for 55 to 200 mm.
- Order it: Designate as Parallel pin ISO 2338 - 6 m6 x 30 - St (A1 for stainless).
ISO 2338 parallel pin dimensions (mm)
Columns: nominal diameter d, tolerance class, end chamfer c (approx.). Length tolerance: ±0.25 (2 to 10 mm), ±0.5 (12 to 50 mm), ±0.75 (55 to 200 mm).
- d | tolerance | c ≈
- 0.6 | m6 or h8 | 0.12
- 0.8 | m6 or h8 | 0.16
- 1 | m6 or h8 | 0.2
- 1.2 | m6 or h8 | 0.25
- 1.5 | m6 or h8 | 0.3
- 2 | m6 or h8 | 0.35
- 2.5 | m6 or h8 | 0.4
- 3 | m6 or h8 | 0.5
- 4 | m6 or h8 | 0.63
- 5 | m6 or h8 | 0.8
- 6 | m6 or h8 | 1.2
- 8 | m6 or h8 | 1.6
- 10 | m6 or h8 | 2
- 12 | m6 or h8 | 2.5
- 16 | m6 or h8 | 3
- 20 | m6 or h8 | 3.5
- 25 | m6 or h8 | 4
- 30 | m6 or h8 | 5
- 40 | m6 or h8 | 6.3
- 50 | m6 or h8 | 8
Worked example: 6 mm parallel pin
A 6 m6 x 30 ISO 2338 pin goes in a 6 H7 hole as a press fit, has about a 1.2 mm end chamfer, and its length may be 29.5 to 30.5 mm.
Common problems
- Pin galls in a hardened part: use a hardened ISO 8734 pin.
- Pin falls out: h8 is too loose for a press fit; use m6 in H7.
- Pin will not come out of a blind hole: use a pin with an internal thread (ISO 8735) or vent the hole.
FAQ
What is ISO 2338?
Unhardened steel or austenitic stainless parallel pins, 0.6 to 50 mm, tolerance m6 or h8. It replaced DIN 7.
How is it different from ISO 8734 dowel pins?
ISO 8734 pins are hardened and ground. ISO 2338 pins are unhardened and are not for hardened parts.
Are old DIN 7 chamfers the same?
No. Old DIN 7 listed a max chamfer (e.g. 0.6 mm at 4 mm) where ISO gives an approximate one (0.63 mm). Only one source gave the DIN values, so they are not shown.
Why are no length ranges per diameter shown?
The ISO preview shows the commercial length range as a graphic that cannot be read, and the sources did not agree, so the per-diameter ranges were left out. Nominal lengths run 2 to 200 mm, then in 20 mm steps.
What was skipped?
Per-diameter length ranges, the old DIN 7 chamfers, the end radius r, and the m6/h8 limits in microns (look up m6/h8 in ISO 286).
Related guides and calculators
- Clevis pins with threaded end (DIN 1445)
- Light-duty coiled spring pins (ISO 8751)
- Headless clevis pins (ISO 2340 / DIN 1434)
- Round head grooved pins (ISO 8746)
- Grooved pins with pilot (ISO 8739)
- Parallel grooved pins (ISO 8740 / DIN 1473)
- Threaded taper pins (ISO 8737 / DIN 7977)
- Light-duty spring pins (ISO 13337 / DIN 7346)
- Threaded dowel pins (ISO 8735 / DIN 7979)
- Metric dowel pin chart (ISO 8734)
- Metric taper pin chart (ISO 2339)
- Metric clevis pins (ISO 2341 / DIN 1444)
- Slotted spring pin chart (ISO 8752)
- Coiled spring pin chart (ISO 8748)
- ISO 286 hole basis fits explained
- All free machinist calculators
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