K7/h6 fit — Locational transition (shaft basis)
ISO 286 shaft-basis transition fit. Enter a nominal size to get the limits.
About K7/h6
Shaft-basis equivalent of H7/k6, e.g. ball-bearing outer rings in housings.
At Ø25 mm the hole K7 measures −0.015 mm to +0.006 mm and the shaft h6 −0.013 mm to 0 mm, giving between 0.015 mm interference and 0.019 mm clearance.
How the limits are calculated
Hole K7: fundamental deviation ES/EI per ISO 286-1 Table 2, standard tolerance IT7 = 21 µm for 18–30 mm. Shaft h6: fundamental deviation es = 0, IT6 = 13 µm. Clearance = hole − shaft, evaluated at both extremes. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.
K7/h6 limits by size range
| Size (mm) | Hole K7 | Shaft h6 | Clearance min | Clearance max |
|---|---|---|---|---|
| ≤ 3 | 0 / −0.010 | 0 / −0.006 | −0.010 | +0.006 |
| 3 – 6 | +0.003 / −0.009 | 0 / −0.008 | −0.009 | +0.011 |
| 6 – 10 | +0.005 / −0.010 | 0 / −0.009 | −0.010 | +0.014 |
| 10 – 18 | +0.006 / −0.012 | 0 / −0.011 | −0.012 | +0.017 |
| 18 – 30 | +0.006 / −0.015 | 0 / −0.013 | −0.015 | +0.019 |
| 30 – 50 | +0.007 / −0.018 | 0 / −0.016 | −0.018 | +0.023 |
| 50 – 80 | +0.009 / −0.021 | 0 / −0.019 | −0.021 | +0.028 |
| 80 – 120 | +0.010 / −0.025 | 0 / −0.022 | −0.025 | +0.032 |
| 120 – 180 | +0.012 / −0.028 | 0 / −0.025 | −0.028 | +0.037 |
| 180 – 250 | +0.013 / −0.033 | 0 / −0.029 | −0.033 | +0.042 |
| 250 – 315 | +0.016 / −0.036 | 0 / −0.032 | −0.036 | +0.048 |
| 315 – 400 | +0.017 / −0.040 | 0 / −0.036 | −0.040 | +0.053 |
| 400 – 500 | +0.018 / −0.045 | 0 / −0.040 | −0.045 | +0.058 |
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 K7/h6 a clearance fit?
Not always — K7/h6 is a transition fit per ISO 286 (see types of fits). At Ø25 mm it gives between 0.015 mm mm interference and 0.019 mm mm clearance, depending which parts of the tolerance zones are paired.
What is the K7/h6 tolerance at 25 mm?
At a nominal size of Ø25 mm, K7 allows a hole diameter from 24.985 to 25.006 mm, and h6 allows a shaft diameter from 24.987 to 25.000 mm.