G6/h5 fit — Precision sliding fit (shaft basis)
ISO 286 shaft-basis clearance fit. Enter a nominal size to get the limits.
About G6/h5
Shaft-basis equivalent of H6/g5, built around a ground reference shaft rather than a reamed hole: gauge blocks, instrument slides, precision jig components.
At Ø25 mm the hole G6 measures +0.007 mm to +0.020 mm and the shaft h5 −0.009 mm to 0 mm, giving a clearance of 0.007 mm to 0.029 mm.
How the limits are calculated
Hole G6: fundamental deviation ES/EI per ISO 286-1 Table 2, standard tolerance IT6 = 13 µm for 18–30 mm. Shaft h5: fundamental deviation es = 0, IT5 = 9 µm. Clearance = hole − shaft, evaluated at both extremes. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.
G6/h5 limits by size range
| Size (mm) | Hole G6 | Shaft h5 | Clearance min | Clearance max |
|---|---|---|---|---|
| ≤ 3 | +0.008 / +0.002 | 0 / −0.004 | +0.002 | +0.012 |
| 3 – 6 | +0.012 / +0.004 | 0 / −0.005 | +0.004 | +0.017 |
| 6 – 10 | +0.014 / +0.005 | 0 / −0.006 | +0.005 | +0.020 |
| 10 – 18 | +0.017 / +0.006 | 0 / −0.008 | +0.006 | +0.025 |
| 18 – 30 | +0.020 / +0.007 | 0 / −0.009 | +0.007 | +0.029 |
| 30 – 50 | +0.025 / +0.009 | 0 / −0.011 | +0.009 | +0.036 |
| 50 – 80 | +0.029 / +0.010 | 0 / −0.013 | +0.010 | +0.042 |
| 80 – 120 | +0.034 / +0.012 | 0 / −0.015 | +0.012 | +0.049 |
| 120 – 180 | +0.039 / +0.014 | 0 / −0.018 | +0.014 | +0.057 |
| 180 – 250 | +0.044 / +0.015 | 0 / −0.020 | +0.015 | +0.064 |
| 250 – 315 | +0.049 / +0.017 | 0 / −0.023 | +0.017 | +0.072 |
| 315 – 400 | +0.054 / +0.018 | 0 / −0.025 | +0.018 | +0.079 |
| 400 – 500 | +0.060 / +0.020 | 0 / −0.027 | +0.020 | +0.087 |
Deviations in mm at the upper end of each range; negative clearance = interference. Clearance columns are shown on wider screens. Sub-ranges (e.g. 18–24 / 24–30) can differ for r, s, t, u, v, x, y, z — use the calculator for the exact size. “—” means ISO 286 doesn't define this class below that size (e.g. t only starts at 24 mm).
Is G6/h5 a clearance fit?
Yes — G6/h5 is a clearance fit per ISO 286 (see types of fits). At Ø25 mm it gives a clearance of 0.007 mm to 0.029 mm mm, depending which parts of the tolerance zones are paired.
What is the G6/h5 tolerance at 25 mm?
At a nominal size of Ø25 mm, G6 allows a hole diameter from 25.007 to 25.020 mm, and h5 allows a shaft diameter from 24.991 to 25.000 mm.