H7/s6 fit — Medium drive fit

ISO 286 hole-basis interference fit. Enter a nominal size to get the limits.

Nominal size

Unit

Result

Ø25.000 H7/s6Interference fit

	Upper	Lower	Max	Min	Tol.
Hole H7	+0.021	0	25.021	25.000	0.021
Shaft s6	+0.048	+0.035	25.048	25.035	0.013

Max interference: 0.048 mm
Min interference: 0.014 mm
Mean: −0.031 mm

Fit diagram (µm · zero line = nominal)

Hole tolerance zoneShaft tolerance zoneInterference

About H7/s6

Permanent press fit for steel parts transmitting torque without keys: gear rims, bearing bushes, shaft-hub connections.

At Ø25 mm the hole H7 measures 0 mm to +0.021 mm and the shaft s6 +0.035 mm to +0.048 mm, giving an interference of 0.014 mm to 0.048 mm.

How the limits are calculated

Hole H7: fundamental deviation EI = 0, standard tolerance IT7 = 21 µm for 18–30 mm. Shaft s6: fundamental deviation ei = 35 µm, IT6 = 13 µm. Clearance = hole − shaft, evaluated at both extremes. Values per ISO 286-1:2010.

H7/s6 limits by size range

Size (mm)	Hole H7	Shaft s6	Clearance min	Clearance max
≤ 3	+0.010 / 0	+0.020 / +0.014	−0.020	−0.004
3 – 6	+0.012 / 0	+0.027 / +0.019	−0.027	−0.007
6 – 10	+0.015 / 0	+0.032 / +0.023	−0.032	−0.008
10 – 18	+0.018 / 0	+0.039 / +0.028	−0.039	−0.010
18 – 30	+0.021 / 0	+0.048 / +0.035	−0.048	−0.014
30 – 50	+0.025 / 0	+0.059 / +0.043	−0.059	−0.018
50 – 80	+0.030 / 0	+0.078 / +0.059	−0.078	−0.029
80 – 120	+0.035 / 0	+0.101 / +0.079	−0.101	−0.044
120 – 180	+0.040 / 0	+0.133 / +0.108	−0.133	−0.068
180 – 250	+0.046 / 0	+0.169 / +0.140	−0.169	−0.094
250 – 315	+0.052 / 0	+0.202 / +0.170	−0.202	−0.118
315 – 400	+0.057 / 0	+0.244 / +0.208	−0.244	−0.151
400 – 500	+0.063 / 0	+0.292 / +0.252	−0.292	−0.189

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.