N7/h6 fit — Locational transition (shaft basis)

ISO 286 shaft-basis transition fit. Enter a nominal size to get the limits.

Nominal size

Unit

Result

Ø25.000 N7/h6Transition fit

	Upper	Lower	Max	Min	Tol.
Hole N7	−0.007	−0.028	24.993	24.972	0.021
Shaft h6	0	−0.013	25.000	24.987	0.013

Max clearance: 0.006 mm
Max interference: 0.028 mm
Mean: −0.011 mm

Fit diagram (µm · zero line = nominal)

Hole tolerance zoneShaft tolerance zoneClearanceInterference

About N7/h6

Shaft-basis equivalent of H7/n6; common for bearing outer rings under rotating outer-ring load.

At Ø25 mm the hole N7 measures −0.028 mm to −0.007 mm and the shaft h6 −0.013 mm to 0 mm, giving between 0.028 mm interference and 0.006 mm clearance.

How the limits are calculated

Hole N7: 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. Values per ISO 286-1:2010.

N7/h6 limits by size range

Size (mm)	Hole N7	Shaft h6	Clearance min	Clearance max
≤ 3	−0.004 / −0.014	0 / −0.006	−0.014	+0.002
3 – 6	−0.004 / −0.016	0 / −0.008	−0.016	+0.004
6 – 10	−0.004 / −0.019	0 / −0.009	−0.019	+0.005
10 – 18	−0.005 / −0.023	0 / −0.011	−0.023	+0.006
18 – 30	−0.007 / −0.028	0 / −0.013	−0.028	+0.006
30 – 50	−0.008 / −0.033	0 / −0.016	−0.033	+0.008
50 – 80	−0.009 / −0.039	0 / −0.019	−0.039	+0.010
80 – 120	−0.010 / −0.045	0 / −0.022	−0.045	+0.012
120 – 180	−0.012 / −0.052	0 / −0.025	−0.052	+0.013
180 – 250	−0.014 / −0.060	0 / −0.029	−0.060	+0.015
250 – 315	−0.014 / −0.066	0 / −0.032	−0.066	+0.018
315 – 400	−0.016 / −0.073	0 / −0.036	−0.073	+0.020
400 – 500	−0.017 / −0.080	0 / −0.040	−0.080	+0.023

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.