Tolerance chart
js6 tolerance (shaft): ISO 286 chart up to 500 mm
js6 is an ISO tolerance class for shafts (external features) under ISO 286. At Ø25 mm it means +6.5 / −6.5 µm: the size may lie between 24.9935 and 25.0065 mm. Below are the deviations for every nominal size up to 500 mm and the fits that use js6.
js6 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 | +3 | −3 | 6 |
| 3 – 6 | +4 | −4 | 8 |
| 6 – 10 | +4.5 | −4.5 | 9 |
| 10 – 18 | +5.5 | −5.5 | 11 |
| 18 – 30 | +6.5 | −6.5 | 13 |
| 30 – 50 | +8 | −8 | 16 |
| 50 – 80 | +9.5 | −9.5 | 19 |
| 80 – 120 | +11 | −11 | 22 |
| 120 – 180 | +12.5 | −12.5 | 25 |
| 180 – 250 | +14.5 | −14.5 | 29 |
| 250 – 315 | +16 | −16 | 32 |
| 315 – 400 | +18 | −18 | 36 |
| 400 – 500 | +20 | −20 | 40 |
js6 for your nominal size
How js6 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 6 is the standard tolerance grade IT6: it sets how wide the zone is – 13 µm at Ø25 mm.
The tolerance grows with the nominal size: 6 µm in the smallest row (0 – 3 mm), 40 µm in the largest (400 – 500 mm). On a drawing the class follows the dimension, as in »Ø25 js6«; the inspection plan turns that into the limits 24.9935 and 25.0065 mm.
Fits with js6 at Ø25 mm
Hole-basis system: the hole is H, the shaft js6. Clearance in µm; a minus means interference. Sorted from the largest minimum clearance to the largest interference.
Frequently asked questions about js6
What does js6 mean?
js6 is an ISO tolerance class for shafts (external features): the letter js sets the position of the tolerance zone, the number 6 the standard tolerance grade IT6. At Ø25 mm that gives +6.5 / −6.5 µm, i.e. 24.9935 to 25.0065 mm.
What are the js6 limits at Ø10 and Ø50 mm?
Ø10 js6: +4.5 / −4.5 µm (9.9955 to 10.0045 mm). Ø50 js6: +8 / −8 µm (49.992 to 50.008 mm).
Is js6 a clearance fit?
A tolerance class on its own is not a fit – only together with its mating part. H7/js6 at Ø25 mm is a transition fit (maximum clearance 27.5 µm, minimum clearance −6.5 µm; a minus means interference).
More tolerance classes
Same letter js, other grades: js5
Shafts in grade 6: h6 · g6 · f6 · k6 · m6 · n6 · p6 · r6 · s6
All classes at a glance: ISO 286 tolerance charts. The same chart in German: js6 Toleranz.