H7/p6 fit — Locational interference

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

Nominal size

Unit

Result

Ø25.000 H7/p6Interference fit

	Upper	Lower	Max	Min	Tol.
Hole H7	+0.021	0	25.021	25.000	0.021
Shaft p6	+0.035	+0.022	25.035	25.022	0.013

Max interference: 0.035 mm
Min interference: 0.001 mm
Mean: −0.018 mm

Fit diagram (µm · zero line = nominal)

Hole tolerance zoneShaft tolerance zoneInterference

About H7/p6

Parts that must stay fixed without transmitting large torque: bushes pressed into housings, dowels, gears on shafts with a key.

At Ø25 mm the hole H7 measures 0 mm to +0.021 mm and the shaft p6 +0.022 mm to +0.035 mm, giving an interference of 0.001 mm to 0.035 mm.

How the limits are calculated

Hole H7: fundamental deviation EI = 0, standard tolerance IT7 = 21 µm for 18–30 mm. Shaft p6: fundamental deviation ei = 22 µm, IT6 = 13 µm. Clearance = hole − shaft, evaluated at both extremes. Values per ISO 286-1:2010.

H7/p6 limits by size range

Size (mm)	Hole H7	Shaft p6	Clearance min	Clearance max
≤ 3	+0.010 / 0	+0.012 / +0.006	−0.012	+0.004
3 – 6	+0.012 / 0	+0.020 / +0.012	−0.020	0
6 – 10	+0.015 / 0	+0.024 / +0.015	−0.024	0
10 – 18	+0.018 / 0	+0.029 / +0.018	−0.029	0
18 – 30	+0.021 / 0	+0.035 / +0.022	−0.035	−0.001
30 – 50	+0.025 / 0	+0.042 / +0.026	−0.042	−0.001
50 – 80	+0.030 / 0	+0.051 / +0.032	−0.051	−0.002
80 – 120	+0.035 / 0	+0.059 / +0.037	−0.059	−0.002
120 – 180	+0.040 / 0	+0.068 / +0.043	−0.068	−0.003
180 – 250	+0.046 / 0	+0.079 / +0.050	−0.079	−0.004
250 – 315	+0.052 / 0	+0.088 / +0.056	−0.088	−0.004
315 – 400	+0.057 / 0	+0.098 / +0.062	−0.098	−0.005
400 – 500	+0.063 / 0	+0.108 / +0.068	−0.108	−0.005

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.