Tolerance chart
js5 tolerance (shaft): ISO 286 chart up to 500 mm
js5 is an ISO tolerance class for shafts (external features) under ISO 286. At Ø25 mm it means +4.5 / −4.5 µm: the size may lie between 24.9955 and 25.0045 mm. Below are the deviations for every nominal size up to 500 mm and the fits that use js5.
js5 chart: deviations for all nominal sizes up to 500 mm
Deviations in µm (1 µm = 0.001 mm). A nominal size belongs to the row »over … up to and including …«: exactly 30 mm is in the row ending at 30, 30.1 mm in the next one.
| Nominal size over – to (mm) | Upper deviation | Lower deviation | Tolerance |
|---|---|---|---|
| 0 – 3 | +2 | −2 | 4 |
| 3 – 6 | +2.5 | −2.5 | 5 |
| 6 – 10 | +3 | −3 | 6 |
| 10 – 18 | +4 | −4 | 8 |
| 18 – 30 | +4.5 | −4.5 | 9 |
| 30 – 50 | +5.5 | −5.5 | 11 |
| 50 – 80 | +6.5 | −6.5 | 13 |
| 80 – 120 | +7.5 | −7.5 | 15 |
| 120 – 180 | +9 | −9 | 18 |
| 180 – 250 | +10 | −10 | 20 |
| 250 – 315 | +11.5 | −11.5 | 23 |
| 315 – 400 | +12.5 | −12.5 | 25 |
| 400 – 500 | +13.5 | −13.5 | 27 |
js5 for your nominal size
How js5 is built
An ISO tolerance class is a letter and a number. Capital letters stand for holes, small letters for shafts. The letter js sets the position of the tolerance zone; at Ø25 mm it lies symmetrically around the nominal size. The number 5 is the standard tolerance grade IT5: it sets how wide the zone is – 9 µm at Ø25 mm.
The tolerance grows with the nominal size: 4 µm in the smallest row (0 – 3 mm), 27 µm in the largest (400 – 500 mm). On a drawing the class follows the dimension, as in »Ø25 js5«; the inspection plan turns that into the limits 24.9955 and 25.0045 mm.
Fits with js5 at Ø25 mm
Hole-basis system: the hole is H, the shaft js5. Clearance in µm; a minus means interference. Sorted from the largest minimum clearance to the largest interference.
| Fit | Type | Max. clearance | Min. clearance |
|---|---|---|---|
| H6/js5 | transition fit | 17.5 | −4.5 |
Frequently asked questions about js5
What does js5 mean?
js5 is an ISO tolerance class for shafts (external features): the letter js sets the position of the tolerance zone, the number 5 the standard tolerance grade IT5. At Ø25 mm that gives +4.5 / −4.5 µm, i.e. 24.9955 to 25.0045 mm.
What are the js5 limits at Ø10 and Ø50 mm?
Ø10 js5: +3 / −3 µm (9.997 to 10.003 mm). Ø50 js5: +5.5 / −5.5 µm (49.9945 to 50.0055 mm).
Is js5 a clearance fit?
A tolerance class on its own is not a fit – only together with its mating part. H6/js5 at Ø25 mm is a transition fit (maximum clearance 17.5 µm, minimum clearance −4.5 µm; a minus means interference).
More tolerance classes
Same letter js, other grades: js6
Shafts in grade 5: h5 · g5 · k5 · m5 · n5
All classes at a glance: ISO 286 tolerance charts. The same chart in German: js5 Toleranz.