js7 tolerance (shaft, IT7)
Shaft tolerance class js7 per ISO 286-1:2010: fundamental deviation ±IT/2, grade IT7 (10 µm at ≤ 3 mm to 63 µm at 400–500 mm). For an exact size, open the calculator with js7 selected.
- Type
- Shaft
- Grade
- IT7
- Tolerance
- 10 … 63 µm
- Fund. deviation
- ±IT/2
js7 limits by size range
| Size (mm) | Upper (µm) | Lower (µm) | Ø max (mm) | Ø min (mm) | Upper (mm) | Lower (mm) | Dev. (in) |
|---|---|---|---|---|---|---|---|
| ≤ 3 | +5 | −5 | 3.005 | 2.995 | +0.0050 | −0.0050 | +0.00020 / −0.00020 |
| 3 – 6 | +6 | −6 | 6.006 | 5.994 | +0.0060 | −0.0060 | +0.00024 / −0.00024 |
| 6 – 10 | +7.5 | −7.5 | 10.0075 | 9.9925 | +0.0075 | −0.0075 | +0.00030 / −0.00030 |
| 10 – 14 | +9 | −9 | 14.009 | 13.991 | +0.0090 | −0.0090 | +0.00035 / −0.00035 |
| 14 – 18 | +9 | −9 | 18.009 | 17.991 | +0.0090 | −0.0090 | +0.00035 / −0.00035 |
| 18 – 24 | +10.5 | −10.5 | 24.0105 | 23.9895 | +0.0105 | −0.0105 | +0.00041 / −0.00041 |
| 24 – 30 | +10.5 | −10.5 | 30.0105 | 29.9895 | +0.0105 | −0.0105 | +0.00041 / −0.00041 |
| 30 – 40 | +12.5 | −12.5 | 40.0125 | 39.9875 | +0.0125 | −0.0125 | +0.00049 / −0.00049 |
| 40 – 50 | +12.5 | −12.5 | 50.0125 | 49.9875 | +0.0125 | −0.0125 | +0.00049 / −0.00049 |
| 50 – 65 | +15 | −15 | 65.015 | 64.985 | +0.0150 | −0.0150 | +0.00059 / −0.00059 |
| 65 – 80 | +15 | −15 | 80.015 | 79.985 | +0.0150 | −0.0150 | +0.00059 / −0.00059 |
| 80 – 100 | +17.5 | −17.5 | 100.0175 | 99.9825 | +0.0175 | −0.0175 | +0.00069 / −0.00069 |
| 100 – 120 | +17.5 | −17.5 | 120.0175 | 119.9825 | +0.0175 | −0.0175 | +0.00069 / −0.00069 |
| 120 – 140 | +20 | −20 | 140.020 | 139.980 | +0.0200 | −0.0200 | +0.00079 / −0.00079 |
| 140 – 160 | +20 | −20 | 160.020 | 159.980 | +0.0200 | −0.0200 | +0.00079 / −0.00079 |
| 160 – 180 | +20 | −20 | 180.020 | 179.980 | +0.0200 | −0.0200 | +0.00079 / −0.00079 |
| 180 – 200 | +23 | −23 | 200.023 | 199.977 | +0.0230 | −0.0230 | +0.00091 / −0.00091 |
| 200 – 225 | +23 | −23 | 225.023 | 224.977 | +0.0230 | −0.0230 | +0.00091 / −0.00091 |
| 225 – 250 | +23 | −23 | 250.023 | 249.977 | +0.0230 | −0.0230 | +0.00091 / −0.00091 |
| 250 – 280 | +26 | −26 | 280.026 | 279.974 | +0.0260 | −0.0260 | +0.00102 / −0.00102 |
| 280 – 315 | +26 | −26 | 315.026 | 314.974 | +0.0260 | −0.0260 | +0.00102 / −0.00102 |
| 315 – 355 | +28.5 | −28.5 | 355.0285 | 354.9715 | +0.0285 | −0.0285 | +0.00112 / −0.00112 |
| 355 – 400 | +28.5 | −28.5 | 400.0285 | 399.9715 | +0.0285 | −0.0285 | +0.00112 / −0.00112 |
| 400 – 450 | +31.5 | −31.5 | 450.0315 | 449.9685 | +0.0315 | −0.0315 | +0.00124 / −0.00124 |
| 450 – 500 | +31.5 | −31.5 | 500.0315 | 499.9685 | +0.0315 | −0.0315 | +0.00124 / −0.00124 |
Deviations at the upper end of each range (Ø columns use that size); use the calculator for the exact size. — : not defined by ISO 286 for that size. Upper/Lower (mm) and inch columns are shown on wider screens.
About js7
js7 denotes a shaft tolerance zone with symmetric ±IT/2 deviation in the ISO 286 system. It is used in H8/js7 (Symmetric transition fit (equal chance of clearance or interference) on an IT8 hole for lower-cost locational assemblies that still need accurate centring: fixture plates, coarse gear-on-shaft assemblies.).
At Ø25 mm js7 is +0.0105 / −0.0105 mm, i.e. 24.9895 to 25.0105 mm.
How the limits are calculated
js7 uses grade IT7 (a standard tolerance of 21 µm at 18–30 mm). Fundamental deviation: ±IT7/2: the tolerance zone is centred on the nominal size. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.