H7/js6 fit — Locational transition

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

Nominal size

Unit

Result

Ø25.000 H7/js6Transition fit

	Upper	Lower	Max	Min	Tol.
Hole H7	+0.021	0	25.021	25.000	0.021
Shaft js6	+0.0065	−0.0065	25.0065	24.9935	0.013

Max clearance: 0.0275 mm
Max interference: 0.0065 mm
Mean: +0.0105 mm

Fit diagram (µm · zero line = nominal)

Hole tolerance zoneShaft tolerance zoneClearanceInterference

About H7/js6

Parts that need accurate location and easy assembly with a light hammer: pulleys, hand-wheels, couplings.

At Ø25 mm the hole H7 measures 0 mm to +0.021 mm and the shaft js6 −0.0065 mm to +0.0065 mm, giving between 0.0065 mm interference and 0.0275 mm clearance.

How the limits are calculated

Hole H7: fundamental deviation EI = 0, standard tolerance IT7 = 21 µm for 18–30 mm. Shaft js6: fundamental deviation ei = -6.5 µm, IT6 = 13 µm. Clearance = hole − shaft, evaluated at both extremes. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.

H7/js6 limits by size range

Size (mm)	Hole H7	Shaft js6	Clearance min	Clearance max
≤ 3	+0.010 / 0	+0.003 / −0.003	−0.003	+0.013
3 – 6	+0.012 / 0	+0.004 / −0.004	−0.004	+0.016
6 – 10	+0.015 / 0	+0.0045 / −0.0045	−0.0045	+0.0195
10 – 18	+0.018 / 0	+0.0055 / −0.0055	−0.0055	+0.0235
18 – 30	+0.021 / 0	+0.0065 / −0.0065	−0.0065	+0.0275
30 – 50	+0.025 / 0	+0.008 / −0.008	−0.008	+0.033
50 – 80	+0.030 / 0	+0.0095 / −0.0095	−0.0095	+0.0395
80 – 120	+0.035 / 0	+0.011 / −0.011	−0.011	+0.046
120 – 180	+0.040 / 0	+0.0125 / −0.0125	−0.0125	+0.0525
180 – 250	+0.046 / 0	+0.0145 / −0.0145	−0.0145	+0.0605
250 – 315	+0.052 / 0	+0.016 / −0.016	−0.016	+0.068
315 – 400	+0.057 / 0	+0.018 / −0.018	−0.018	+0.075
400 – 500	+0.063 / 0	+0.020 / −0.020	−0.020	+0.083

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 H7/js6 a clearance fit?

Not always — H7/js6 is a transition fit per ISO 286 (see types of fits). At Ø25 mm it gives between 0.0065 mm mm interference and 0.0275 mm mm clearance, depending which parts of the tolerance zones are paired.

What is the H7/js6 tolerance at 25 mm?

At a nominal size of Ø25 mm, H7 allows a hole diameter from 25.000 to 25.021 mm, and js6 allows a shaft diameter from 24.9935 to 25.0065 mm.