Tolerance chart
m5 tolerance (shaft): ISO 286 chart up to 500 mm
m5 is an ISO tolerance class for shafts (external features) under ISO 286. At Ø25 mm it means +17 / +8 µm: the size may lie between 25.008 and 25.017 mm. Below are the deviations for every nominal size up to 500 mm and the fits that use m5.
m5 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 | +6 | +2 | 4 |
| 3 – 6 | +9 | +4 | 5 |
| 6 – 10 | +12 | +6 | 6 |
| 10 – 18 | +15 | +7 | 8 |
| 18 – 30 | +17 | +8 | 9 |
| 30 – 50 | +20 | +9 | 11 |
| 50 – 80 | +24 | +11 | 13 |
| 80 – 120 | +28 | +13 | 15 |
| 120 – 180 | +33 | +15 | 18 |
| 180 – 250 | +37 | +17 | 20 |
| 250 – 315 | +43 | +20 | 23 |
| 315 – 400 | +46 | +21 | 25 |
| 400 – 500 | +50 | +23 | 27 |
m5 for your nominal size
How m5 is built
An ISO tolerance class is a letter and a number. Capital letters stand for holes, small letters for shafts. The letter m sets the position of the tolerance zone; at Ø25 mm it lies entirely above the nominal size: the shaft is always larger than nominal. 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 m5«; the inspection plan turns that into the limits 25.008 and 25.017 mm.
Fits with m5 at Ø25 mm
Hole-basis system: the hole is H, the shaft m5. Clearance in µm; a minus means interference. Sorted from the largest minimum clearance to the largest interference.
| Fit | Type | Max. clearance | Min. clearance |
|---|---|---|---|
| H6/m5 | transition fit | 5 | −17 |
Frequently asked questions about m5
What does m5 mean?
m5 is an ISO tolerance class for shafts (external features): the letter m sets the position of the tolerance zone, the number 5 the standard tolerance grade IT5. At Ø25 mm that gives +17 / +8 µm, i.e. 25.008 to 25.017 mm.
What are the m5 limits at Ø10 and Ø50 mm?
Ø10 m5: +12 / +6 µm (10.006 to 10.012 mm). Ø50 m5: +20 / +9 µm (50.009 to 50.020 mm).
Is m5 a clearance fit?
A tolerance class on its own is not a fit – only together with its mating part. H6/m5 at Ø25 mm is a transition fit (maximum clearance 5 µm, minimum clearance −17 µm; a minus means interference).
More tolerance classes
Same letter m, other grades: m6
Shafts in grade 5: h5 · g5 · js5 · k5 · n5
All classes at a glance: ISO 286 tolerance charts. The same chart in German: m5 Toleranz.