Recommended shaft and housing tolerance classes for rolling bearings, depending on whether the inner ring rotates on the shaft or the outer ring rotates in the housing.
| Shaft tolerance | — |
| Housing tolerance | — |
Typical recommendations per ISO 286 / bearing-fit practice. Tighter classes (e.g. k5, m5) for heavy/impact loads; looser (g6, h6) for easy mounting.
| Condition | Shaft | Housing bore |
|---|---|---|
| Rotating inner ring, normal load | k5, k6, m5, m6 | H7, H8, G7 |
| Rotating inner ring, heavy / impact load | m5, m6, n6 | H7 |
| Stationary inner ring, rotating housing | g6, h6 | J7, K7, M7 |
| Precision / high speed | k5, js5 | H5, H6 |
| Easy mounting / frequent dismount | h6, j6 | H7, H8 |