# Hex flange nuts, DIN 6923: M3–M20 across flats, flange diameter, height, flange thickness + M5–M16 envelope files

> What are the dimensions of a DIN 6923 flange nut, and how wide is an M8 flange nut?

- Category: Hardware › Fasteners
- Kind: Standard part
- Basis: Westfield Fasteners' DIN 6923 table (M5 to M20) and Kanebridge's sheet (M3 to M12); the two agree on s, m and the flange diameter wherever both give a value; six envelope files
- Page: https://xemstudio.com/objects/flange-nuts-din-6923/ · JSON: https://xemstudio.com/api/geometry?object=flange-nuts-din-6923 · Plain text: https://xemstudio.com/objects/flange-nuts-din-6923/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 34.5 | 34.5 | 16.0 |

**Exact dimensions.** Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part.

## Notes

- DIN 6923 is the hexagon nut with a plain (non-serrated) flange. Westfield columns (mm): p pitch; c flange thickness (min); da bearing inner diameter (min / max); dc flange diameter (max); dw outer bearing diameter (min); e across corners (min); m nut height (max / min); s width across flats (max / min). Sizes in brackets are reference only: the page says M3 and M4 are not made to DIN 6923 and gives no bearing diameters or heights for them.
- Kanebridge's sheet (F across flats max / min, H overall height max / min, B flange diameter max) agrees with Westfield on s, m and the flange diameter for M5 to M12 (e.g. M8: 13, 8.0 / 7.6, 17.9; M12: 18, 12.0 / 11.6, 26.0). Kanebridge prints M3 and M4 values (5.5 / 4.0 / 8.0 and 7.0 / 4.65 / 10.0) that agree with Westfield's reference-only figures for the across-flats size and (M4) height, but its M3 flange diameter is 8.0 against 7.8 and the page does not state units.
- Files are Xem-drawn envelopes of sizes M5, M6, M8, M10, M12 and M16: a hexagon of width across flats s max, a circular flange of dc max by c min at the base, overall height m max, plain bore at the nominal thread diameter. The flange-to-body transition, chamfers and the serrated-flange variant are not modelled. Flange thickness c is a minimum, so a real flange may be thicker.
- ISO 4161 and the serrated flange (DIN 6923 with serration) are not tabulated here. McMaster-Carr sells DIN 6923 flange nuts with per-part STEP; the category is linked, not copied.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| hex body | across flats × height: M5 8 × 5, M6 10 × 6, M8 13 × 8, M10 15 × 10, M12 18 × 12, M16 24 × 16 mm (max) | hex pocket that captures the nut: width = across flats + your process clearance | slide | flange-nut-din-6923-* |
| flange | Ø11.8, 14.2, 17.9, 21.8, 26, 34.5 mm max × 1, 1.1, 1.2, 1.5, 1.8, 2.4 min thick (M5 to M16) | round counterbore for the flange: Ø = dc + your process clearance | slide | flange-nut-din-6923-* |

## Sizes

| source | thread | p (mm) | c min | da min / max | dc max | dw min | e min | m (height) max / min | s (across flats) max / min |
|---|---|---|---|---|---|---|---|---|---|
| Westfield (reference only) | (M3) | 0.5 | — | — | 7.8 | — | 6.33 | 3.8 | 5.5 |
| Westfield (reference only) | (M4) | 0.7 | — | — | 10 | — | 7.66 | 4.65 | 7 |
| Westfield | M5 | 0.8 | 1 | 5 / 5.75 | 11.8 | 9.8 | 8.79 | 5 / 4.7 | 8 / 7.78 |
| Westfield | M6 | 1 | 1.1 | 6 / 6.75 | 14.2 | 12.2 | 11.05 | 6 / 5.7 | 10 / 9.78 |
| Westfield | M8 | 1.25 | 1.2 | 8 / 8.75 | 17.9 | 15.8 | 14.38 | 8 / 7.6 | 13 / 12.73 |
| Westfield | M10 | 1.5 | 1.5 | 10 / 10.8 | 21.8 | 19.6 | 16.64 | 10 / 9.6 | 15 / 14.73 |
| Westfield | M12 | 1.75 | 1.8 | 12 / 13 | 26 | 23.8 | 20.03 | 12 / 11.6 | 18 / 17.73 |
| Westfield | M14 | 2 | 2.1 | 14 / 15.1 | 29.9 | 27.6 | 23.36 | 14 / 13.3 | 21 / 20.67 |
| Westfield | M16 | 2 | 2.4 | 16 / 17.3 | 34.5 | 31.9 | 26.75 | 16 / 15.3 | 24 / 23.67 |
| Westfield | M20 | 2.5 | 3 | 20 / 21.6 | 42.8 | 39.9 | 32.95 | 20 / 18.9 | 30 / 29.67 |
| Kanebridge | M3 | 0.5 | — | — | 8 | — | — | 4 / 3.4 | 5.5 / 5.3 |
| Kanebridge | M4 | 0.7 | — | — | 10 | — | — | 4.65 / 4.2 | 7 / 6.78 |
| Kanebridge | M5 | 0.8 | — | — | 11.8 | — | — | 5 / 4.7 | 8 / 7.78 |
| Kanebridge | M6 | 1 | — | — | 14.2 | — | — | 6 / 5.7 | 10 / 9.78 |
| Kanebridge | M8 | 1.25 | — | — | 17.9 | — | — | 8 / 7.6 | 13 / 12.73 |
| Kanebridge | M10 | 1.5 | — | — | 21.8 | — | — | 10 / 9.6 | 15 / 14.73 |
| Kanebridge | M12 | 1.75 | — | — | 26 | — | — | 12 / 11.6 | 18 / 17.73 |

## Where the files are

- Westfield Fasteners: [DIN 6923 hexagon flange nuts: c, da, dc, dw, e, m, s, r, M5 to M20 ((M3) and (M4) reference only)](https://www.westfieldfasteners.co.uk/Standards/Nut-HexFlgPln-M.html) — web — Publisher's page; dimensions are facts
- Kanebridge (fastenersresource.com): [DIN 6923 hex flange nuts M3 to M12: pitch, F across flats, H overall height, B flange diameter](https://fastenersresource.com/sites/default/files/products/kanebridge/techsheets/MetDin6923.pdf) — web — Maker data sheet; numbers only
- McMaster-Carr: [DIN 6923 flange nuts (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/din-6923-nuts) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)

## Free STEP/STL (6 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/flange-nuts-din-6923/index.json

- flange-nut-din-6923-m5-s-8-dc-11.8-m-5: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m5-s-8-dc-11.8-m-5.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m5-s-8-dc-11.8-m-5.stl) — M5 DIN 6923 hex flange nut envelope: hex 8 mm across flats (s max), flange Ø11.8 (dc max) × 1 mm (c min) at the base, overall height 5 mm (m max), plain Ø5 bore; no chamfer, serration or thread
- flange-nut-din-6923-m6-s-10-dc-14.2-m-6: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m6-s-10-dc-14.2-m-6.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m6-s-10-dc-14.2-m-6.stl) — M6 DIN 6923 hex flange nut envelope: hex 10 mm across flats (s max), flange Ø14.2 (dc max) × 1.1 mm (c min) at the base, overall height 6 mm (m max), plain Ø6 bore; no chamfer, serration or thread
- flange-nut-din-6923-m8-s-13-dc-17.9-m-8: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m8-s-13-dc-17.9-m-8.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m8-s-13-dc-17.9-m-8.stl) — M8 DIN 6923 hex flange nut envelope: hex 13 mm across flats (s max), flange Ø17.9 (dc max) × 1.2 mm (c min) at the base, overall height 8 mm (m max), plain Ø8 bore; no chamfer, serration or thread
- flange-nut-din-6923-m10-s-15-dc-21.8-m-10: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m10-s-15-dc-21.8-m-10.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m10-s-15-dc-21.8-m-10.stl) — M10 DIN 6923 hex flange nut envelope: hex 15 mm across flats (s max), flange Ø21.8 (dc max) × 1.5 mm (c min) at the base, overall height 10 mm (m max), plain Ø10 bore; no chamfer, serration or thread
- flange-nut-din-6923-m12-s-18-dc-26-m-12: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m12-s-18-dc-26-m-12.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m12-s-18-dc-26-m-12.stl) — M12 DIN 6923 hex flange nut envelope: hex 18 mm across flats (s max), flange Ø26 (dc max) × 1.8 mm (c min) at the base, overall height 12 mm (m max), plain Ø12 bore; no chamfer, serration or thread
- flange-nut-din-6923-m16-s-24-dc-34.5-m-16: [STEP](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m16-s-24-dc-34.5-m-16.step) · [STL](https://xemstudio.com/files/hardware/flange-nuts-din-6923/flange-nut-din-6923-m16-s-24-dc-34.5-m-16.stl) — M16 DIN 6923 hex flange nut envelope: hex 24 mm across flats (s max), flange Ø34.5 (dc max) × 2.4 mm (c min) at the base, overall height 16 mm (m max), plain Ø16 bore; no chamfer, serration or thread

## Questions

**How wide is an M8 flange nut?**

13 mm across flats, flange 17.9 mm maximum, height 8 mm max / 7.6 min, flange thickness at least 1.2 mm (Westfield; Kanebridge agrees).

**Why does an M10 flange nut take a 15 mm wrench?**

DIN 6923 uses s = 15 mm for M10 (and 18 for M12), smaller than the 16 and 18 of the plain ISO 4032 nut.

## Fits with

- [Hex nuts, M2–M8 (ISO 4032)](https://xemstudio.com/objects/hex-nuts-metric/)
- [Hex nuts, M10 to M24 (ISO 4032 / DIN 934)](https://xemstudio.com/objects/hex-nuts-metric-m10-m24/)
- [Nylon-insert lock nuts (nyloc), ISO 7040 and DIN 985, M3–M36: width across flats, height, bearing diameter + M10–M30 envelope files](https://xemstudio.com/objects/nylon-insert-lock-nuts-iso-7040-din-985/)
- [Flat washers, M2–M8 (ISO 7089)](https://xemstudio.com/objects/flat-washers-metric/)
- [Large (fender) washers, DIN 9021 / ISO 7093: M2.5–M36 bore, outside diameter, thickness + nylon variant + 8 washer files](https://xemstudio.com/objects/large-washers-din-9021-iso-7093/)
- [Square nuts, DIN 557: M5–M20 width across flats, thickness, corner distance + 8 envelope files](https://xemstudio.com/objects/square-nuts-din-557/)