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ISO 286 Fit & Tolerance Calculator
Look up ISO 286 limits and the fit for a hole-basis pair such as H7/g6. Values are the ISO 286-1:2010 standard tolerances (IT5–IT11) and fundamental deviations for nominal sizes above 0 up to 500 mm.
Common hole-basis fits
| Fit | Type | Typical use |
|---|---|---|
| H7/f7 | Clearance | Running fit, plain bearings |
| H7/g6 | Clearance | Close sliding / locating fit |
| H7/h6 | Clearance (zero minimum) | Locating fit, parts assembled by hand |
| H7/k6 | Transition | Accurate location, light press or tap fit |
| H7/n6 | Transition | Firmer location, light press |
| H7/p6 | Interference | Press fit, location with interference |
Worked example: 25 mm H7/g6
For 18–30 mm, IT7 = 21 µm and IT6 = 13 µm; g has es = −7 µm. Hole 25.000 to 25.021 mm; shaft 24.980 to 24.993 mm; clearance 0.007 to 0.041 mm.
Shaft k uses its fundamental deviation for grades 4–7 only (0 for other grades), as ISO 286-1 specifies. Only the listed letters and grades are included because they were checked line by line against ISO 286-1:2010 Tables 1 and 2/3 and two independent public tables (mechsheet.com and mechguru.com). Always confirm critical fits against your drawing and the standard.
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