For Hex Bolts, the M10 thread sits in the small-to-medium range of the catalog and is one of the most-asked hex bolts in this family. The dimensional and assembly data follow.
M10 Dimensional Row (ISO 4014 / ISO 4017)
| Size | Pitch coarse (mm) | Width across flats s (mm) | Width across corners e min (mm) | Head height k nom (mm) | Nominal diameter d (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| M10 | 1.5 | 16.0 | 17.77 | 6.4 | 10.0 | ISO 4014/4017 | Fully threaded |
Spanner & Drive for M10 Hex Bolts
M10 Hex Bolts have a width across flats of 16.0 mm — fit a 16.0 mm open-ended spanner or socket. Use a 6-point socket for tight clearances and to reduce rounding; for repeated assembly choose a torque wrench so the joint preload is repeatable.
Hole Sizes for M10
| Coarse-thread pitch (ISO 724) | 1.5 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 11 mm |
| Tapping drill, coarse thread | 8.5 mm |
Tightening Torque for M10
| Class 8.8 (dry, ~µ 0.125) | ≈ 49 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 69 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 83 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Installation Tips for M10 Hex Bolts
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
Mating Parts for M10
For M10, pair with a M10 hex nut (ISO 4032 / DIN 934) and, where used, a M10 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
When to Step Up or Down from M10
When the joint preload approaches the proof load of M10 class 8.8, step up to M12 class 8.8 (or move to M10 class 10.9). When the joint is over-specified, M8 often saves weight and cost without losing the safety margin.