E8 tolerance (hole, IT8)
Hole tolerance class E8 per ISO 286-1:2010: fundamental deviation EI +14 … +135, grade IT8 (14 µm at ≤ 3 mm to 97 µm at 400–500 mm). For an exact size, open the calculator with E8 selected.
- Type
- Hole
- Grade
- IT8
- Tolerance
- 14 … 97 µm
- Fund. deviation
- EI +14 … +135 µm
E8 limits by size range
| Size (mm) | Upper (µm) | Lower (µm) | Ø max (mm) | Ø min (mm) | Upper (mm) | Lower (mm) | Dev. (in) |
|---|---|---|---|---|---|---|---|
| ≤ 3 | +28 | +14 | 3.028 | 3.014 | +0.028 | +0.014 | +0.00110 / +0.00055 |
| 3 – 6 | +38 | +20 | 6.038 | 6.020 | +0.038 | +0.020 | +0.00150 / +0.00079 |
| 6 – 10 | +47 | +25 | 10.047 | 10.025 | +0.047 | +0.025 | +0.00185 / +0.00098 |
| 10 – 14 | +59 | +32 | 14.059 | 14.032 | +0.059 | +0.032 | +0.00232 / +0.00126 |
| 14 – 18 | +59 | +32 | 18.059 | 18.032 | +0.059 | +0.032 | +0.00232 / +0.00126 |
| 18 – 24 | +73 | +40 | 24.073 | 24.040 | +0.073 | +0.040 | +0.00287 / +0.00157 |
| 24 – 30 | +73 | +40 | 30.073 | 30.040 | +0.073 | +0.040 | +0.00287 / +0.00157 |
| 30 – 40 | +89 | +50 | 40.089 | 40.050 | +0.089 | +0.050 | +0.00350 / +0.00197 |
| 40 – 50 | +89 | +50 | 50.089 | 50.050 | +0.089 | +0.050 | +0.00350 / +0.00197 |
| 50 – 65 | +106 | +60 | 65.106 | 65.060 | +0.106 | +0.060 | +0.00417 / +0.00236 |
| 65 – 80 | +106 | +60 | 80.106 | 80.060 | +0.106 | +0.060 | +0.00417 / +0.00236 |
| 80 – 100 | +126 | +72 | 100.126 | 100.072 | +0.126 | +0.072 | +0.00496 / +0.00283 |
| 100 – 120 | +126 | +72 | 120.126 | 120.072 | +0.126 | +0.072 | +0.00496 / +0.00283 |
| 120 – 140 | +148 | +85 | 140.148 | 140.085 | +0.148 | +0.085 | +0.00583 / +0.00335 |
| 140 – 160 | +148 | +85 | 160.148 | 160.085 | +0.148 | +0.085 | +0.00583 / +0.00335 |
| 160 – 180 | +148 | +85 | 180.148 | 180.085 | +0.148 | +0.085 | +0.00583 / +0.00335 |
| 180 – 200 | +172 | +100 | 200.172 | 200.100 | +0.172 | +0.100 | +0.00677 / +0.00394 |
| 200 – 225 | +172 | +100 | 225.172 | 225.100 | +0.172 | +0.100 | +0.00677 / +0.00394 |
| 225 – 250 | +172 | +100 | 250.172 | 250.100 | +0.172 | +0.100 | +0.00677 / +0.00394 |
| 250 – 280 | +191 | +110 | 280.191 | 280.110 | +0.191 | +0.110 | +0.00752 / +0.00433 |
| 280 – 315 | +191 | +110 | 315.191 | 315.110 | +0.191 | +0.110 | +0.00752 / +0.00433 |
| 315 – 355 | +214 | +125 | 355.214 | 355.125 | +0.214 | +0.125 | +0.00843 / +0.00492 |
| 355 – 400 | +214 | +125 | 400.214 | 400.125 | +0.214 | +0.125 | +0.00843 / +0.00492 |
| 400 – 450 | +232 | +135 | 450.232 | 450.135 | +0.232 | +0.135 | +0.00913 / +0.00531 |
| 450 – 500 | +232 | +135 | 500.232 | 500.135 | +0.232 | +0.135 | +0.00913 / +0.00531 |
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 E8
E8 denotes a hole tolerance zone with running clearance deviation in the ISO 286 system.
At Ø25 mm E8 is +0.073 / +0.040 mm, i.e. 25.040 to 25.073 mm.
How the limits are calculated
E8 uses grade IT8 (a standard tolerance of 33 µm at 18–30 mm). Fundamental deviation: EI = −es of the same shaft letter; IT8 sets the width above EI. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.