TOPNeed Support?
Please provide your question. We’ll find you with the best support options.
⬇️ Scroll Down Now or Contact ISK for More Bearing Information
Table of contents
When it comes to bearings, we often hear the term "ABEC rating," which is used to measure the precision of bearings.
The ABEC (Annular Bearing Engineering Committee) rating system was established by the American Bearing Manufacturers Association to standardize the production and evaluation of bearings, making it easier for consumers to understand and compare bearings of different grades. However, the ABEC rating is not universally applicable to all applications, particularly when it comes to electric bicycles.
ABEC Rating Chart
| ABEC | ISO 492 | DIN 620 | JIS |
| ABEC 1 | Class Normal | P0 | Class 0 |
| ABEC 3 | Class 6 | P6 | Class 6 |
| ABEC 5 | Class 5 | P5 | Class 5 |
| ABEC 7 | Class 4 | P4 | Class 4 |
| ABEC 9 | Class 2 | P2 | Class 2 |
※ The International Organization for Standardization (ISO) standard is ISO 492, the German standard is DIN 620, and the Japanese standard is JIS B1514.
⚠️The ABEC rating ranges from ABEC-1 to ABEC-9, with the number inversely proportional to the tolerance level, meaning that higher numbers indicate lower tolerances. Higher ABEC ratings (lower tolerances) offer better precision, which can potentially impact the smoothness and efficiency of equipment operation, but it doesn't necessarily mean that the bearing-installed components will rotate faster.
The following tables list the actual ABEC tolerances per ABMA Standard 20. The tables list tolerances for both inner and outer rings, in both inch and metric units. These tables are useful in determining sizes and tolerance for components, such as shafts and housings. The designer should always do a tolerance stack up study at both maximum and least material conditions when sizing components, particularly when designing for miniature ball bearings.
Quick Overview of Bearing Precision
(1) P0, ABEC-1 Grade Tolerance (ISO Class Normal)
(2) P6, ABEC-3 Grade Tolerance (ISO Class 6)
(3) P5, ABEC-5 Grade Tolerance (ISO Class 5)
ISK Bearing is of general-purpose, and the tolerance of common bearings of general-purpose (Class 0)is show in table. Please specify in order if customer have any special tolerance requirement.
Inner Ring Of P0, ABEC-1 Grade Tolerance (ISO Class Normal)
|
d mm |
△dmp |
Vdp |
Vdmp |
Kia |
△Bs |
VBS |
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Diameter series |
||||||||||||
|
9 |
0, 1 |
2,3,4 |
all |
normal |
correct |
|||||||
|
over |
incl |
high |
low |
max |
max |
max |
high |
|
low |
max |
||
|
0 |
2 |
0 |
- |
10 |
8 |
6 |
6 |
10 |
0 |
- |
|
12 |
|
2 |
10 |
0 |
- |
10 |
8 |
6 |
6 |
10 |
0 |
- |
- |
15 |
|
10 |
18 |
0 |
- |
10 |
8 |
6 |
6 |
10 |
0 |
- |
- |
20 |
|
18 |
30 |
0 |
- |
13 |
10 |
8 |
8 |
13 |
0 |
- |
- |
20 |
|
30 |
50 |
0 |
- |
15 |
12 |
9 |
9 |
15 |
0 |
- |
- |
20 |
|
50 |
80 |
0 |
- |
19 |
19 |
11 |
11 |
20 |
0 |
- |
- |
25 |
|
80 |
120 |
0 |
- |
25 |
25 |
15 |
15 |
25 |
0 |
- |
- |
25 |
Outer Ring Of P0, ABEC-1 Grade Tolerance (ISO Class Normal)
|
D mm |
△Dmp |
Vdp |
VDmp |
Kea |
△Cs △Cis |
Vcs |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Open Bearing |
Capped |
||||||||||||
|
Diameter series |
|||||||||||||
|
9 |
0, 1 |
2,3,4 |
2,3,4 |
||||||||||
|
over |
incl. |
high |
low |
max. |
max. |
max. |
high |
low |
max. |
||||
|
2.5 |
6 |
0 |
-8 |
10 |
8 |
6 |
10 |
6 |
15 |
Identical to △Bs and VBs of inner ring of same bearing |
|||
|
6 |
18 |
0 |
-8 |
10 |
8 |
6 |
10 |
6 |
15 |
||||
|
18 |
30 |
0 |
-9 |
12 |
9 |
7 |
12 |
7 |
15 |
||||
|
30 |
50 |
0 |
-11 |
14 |
11 |
8 |
16 |
8 |
20 |
||||
|
50 |
80 |
0 |
-13 |
16 |
13 |
10 |
20 |
10 |
25 |
||||
|
80 |
120 |
0 |
-15 |
19 |
19 |
11 |
26 |
11 |
35 |
||||
|
120 |
150 |
0 |
-18 |
23 |
23 |
14 |
30 |
14 |
40 |
||||
|
150 |
180 |
0 |
-25 |
31 |
31 |
19 |
38 |
19 |
45 |
||||
|
180 |
250 |
0 |
-30 |
38 |
38 |
23 |
- |
23 |
50 |
||||
The key to determining the bearing tolerance class lies in the specification of the shaft's rotation accuracy at the support point.
Inner Ring Of P6, ABEC-3 Grade Tolerance (ISO Class 6)
| Bore Diameter (d) | Bore Tolerance (Δdmp) |
Radial Runout (Kia) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 0.6 | 2.5 | 0.0236 | 0.0984 | 0 | -7 | 5 | 0 | -40 | - |
| 2.5 | 10 | 0.0984 | 0.3937 | 0 | -7 | 6 | 0 | -120 | -250 |
| 10 | 18 | 0.3937 | 0.7087 | 0 | -7 | 7 | 0 | -120 | -250 |
| 18 | 30 | 0.7087 | 1.1811 | 0 | -8 | 8 | 0 | -120 | -250 |
| 30 | 50 | 1.1811 | 1.9685 | 0 | -10 | 10 | 0 | -120 | -250 |
| 50 | 80 | 1.9685 | 3.1496 | 0 | -12 | 10 | 0 | -150 | -380 |
| 80 | 120 | 3.1496 | 4.7244 | 0 | -15 | 13 | 0 | -200 | -380 |
| 120 | 180 | 4.7244 | 7.0866 | 0 | -18 | 18 | 0 | -250 | -500 |
| 180 | 250 | 7.0866 | 9.8425 | 0 | -22 | 20 | 0 | -300 | -500 |
| 250 | 315 | 9.8425 | 12.4016 | 0 | -25 | 25 | 0 | -350 | -500 |
| 315 | 400 | 12.4016 | 15.7480 | 0 | -30 | 30 | 0 | -400 | -630 |
Outer Ring Of P6, ABEC-3 Grade Tolerance (ISO Class 6)
| Outer Diameter (D) | Outer Dia. Tolerance (Δdmp) |
Radial Runout (Kea) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 2.5 | 6 | 0.0984 | 0.2362 | 0 | -7 | 8 | Identical to Width Tolerance (ΔBS) of Inner Ring of the same Bearing | ||
| 6 | 18 | 0.2362 | 0.7087 | 0 | -7 | 8 | |||
| 18 | 30 | 0.7087 | 1.1811 | 0 | -8 | 9 | |||
| 30 | 50 | 1.1811 | 1.9685 | 0 | -9 | 10 | |||
| 50 | 80 | 1.9685 | 3.1496 | 0 | -11 | 13 | |||
| 80 | 120 | 3.1496 | 4.7244 | 0 | -13 | 18 | |||
| 120 | 150 | 4.7244 | 5.9055 | 0 | -15 | 20 | |||
| 150 | 180 | 5.9055 | 7.0866 | 0 | -18 | 23 | |||
| 180 | 250 | 7.0866 | 9.8425 | 0 | -20 | 25 | |||
| 250 | 315 | 9.8425 | 12.4016 | 0 | -25 | 30 | |||
| 315 | 400 | 12.4016 | 15.7480 | 0 | -28 | 35 | |||
| 400 | 500 | 15.7480 | 19.6850 | 0 | -33 | 40 | |||
| 500 | 630 | 19.6850 | 24.8031 | 0 | -38 | 50 | |||
| 630 | 800 | 24.8031 | 31.4961 | 0 | -45 | 60 | |||
| 800 | 1000 | 31.4961 | 39.3701 | 0 | -60 | 75 | |||
The key to determining the bearing tolerance class lies in the specification of the shaft's rotation accuracy at the support point.
Inner Ring Of P5, ABEC-5 Grade Tolerance (ISO Class 5)
| Bore Diameter (d) | Bore Tolerance (Δdmp) |
Radial Runout (Kia) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 0.6 | 2.5 | 0.0236 | 0.0984 | 0 | -5 | 4 | 0 | -40 | -250 |
| 2.5 | 10 | 0.0984 | 0.3937 | 0 | -5 | 4 | 0 | -40 | -250 |
| 10 | 18 | 0.3937 | 0.7087 | 0 | -5 | 4 | 0 | -80 | -250 |
| 18 | 30 | 0.7087 | 1.1811 | 0 | -6 | 4 | 0 | -120 | -250 |
| 30 | 50 | 1.1811 | 1.9685 | 0 | -8 | 5 | 0 | -120 | -250 |
| 50 | 80 | 1.9685 | 3.1496 | 0 | -9 | 5 | 0 | -150 | -250 |
| 80 | 120 | 3.1496 | 4.7244 | 0 | -10 | 6 | 0 | -200 | -380 |
| 120 | 180 | 4.7244 | 7.0866 | 0 | -13 | 8 | 0 | -250 | -380 |
| 180 | 250 | 7.0866 | 9.8425 | 0 | -15 | 10 | 0 | -300 | -500 |
| 250 | 315 | 9.8425 | 12.4016 | 0 | -18 | 13 | 0 | -350 | -500 |
| 315 | 400 | 12.4016 | 15.7480 | 0 | -23 | 15 | 0 | -400 | -630 |
Outer Ring Of P5, ABEC-5 Grade Tolerance (ISO Class 5)
| Outer Diameter (D) | Outer Dia. Tolerance (Δdmp) |
Radial Runout (Kea) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 2.5 | 6 | 0.0984 | 0.2362 | 0 | -5 | 5 | Identical to Width Tolerance (ΔBS) of Inner Ring of the same Bearing | ||
| 6 | 18 | 0.2362 | 0.7087 | 0 | -5 | 5 | |||
| 18 | 30 | 0.7087 | 1.1811 | 0 | -6 | 6 | |||
| 30 | 50 | 1.1811 | 1.9685 | 0 | -6 | 6 | |||
| 50 | 80 | 1.9685 | 3.1496 | 0 | -9 | 8 | |||
| 80 | 120 | 3.1496 | 4.7244 | 0 | -10 | 10 | |||
| 120 | 150 | 4.7244 | 5.9055 | 0 | -11 | 11 | |||
| 150 | 180 | 5.9055 | 7.0866 | 0 | -13 | 13 | |||
| 180 | 250 | 7.0866 | 9.8425 | 0 | -15 | 15 | |||
| 250 | 315 | 9.8425 | 12.4016 | 0 | -18 | 18 | |||
| 315 | 400 | 12.4016 | 15.7480 | 0 | -20 | 20 | |||
| 400 | 500 | 15.7480 | 19.6850 | 0 | -23 | 23 | |||
| 500 | 630 | 19.6850 | 24.8031 | 0 | -28 | 25 | |||
| 630 | 800 | 24.8031 | 31.4961 | 0 | -35 | 30 | |||
The key to determining the bearing tolerance class lies in the specification of the shaft's rotation accuracy at the support point.
Inner Ring Of P4, ABEC-7 Grade Tolerance (ISO Class 4)
| Bore Diameter (d) | Bore Tolerance (Δdmp) |
Radial Runout (Kia) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 0.6 | 2.5 | 0.0236 | 0.0984 | 0 | -4 | 2.5 | 0 | -40 | -250 |
| 2.5 | 10 | 0.0984 | 0.3937 | 0 | -4 | 2.5 | 0 | -40 | -250 |
| 10 | 18 | 0.3937 | 0.7087 | 0 | -4 | 2.5 | 0 | -80 | -250 |
| 18 | 30 | 0.7087 | 1.1811 | 0 | -5 | 3 | 0 | -120 | -250 |
| 30 | 50 | 1.1811 | 1.9685 | 0 | -6 | 4 | 0 | -120 | -250 |
| 50 | 80 | 1.9685 | 3.1496 | 0 | -7 | 4 | 0 | -150 | -250 |
| 80 | 120 | 3.1496 | 4.7244 | 0 | -8 | 5 | 0 | -200 | -380 |
| 120 | 180 | 4.7244 | 7.0866 | 0 | -10 | 6 | 0 | -250 | -380 |
| 180 | 250 | 7.0866 | 9.8425 | 0 | -12 | 8 | 0 | -300 | -500 |
Outer Ring Of P4, ABEC-7 Grade Tolerance (ISO Class 4)
| Outer Diameter (D) | Outer Dia. Tolerance (Δdmp) |
Radial Runout (Kea) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 2.5 | 6 | 0.0984 | 0.2362 | 0 | -4 | 3 | Identical to Width Tolerance (ΔBS) of Inner Ring of the same Bearing | ||
| 6 | 18 | 0.2362 | 0.7087 | 0 | -4 | 3 | |||
| 18 | 30 | 0.7087 | 1.1811 | 0 | -5 | 4 | |||
| 30 | 50 | 1.1811 | 1.9685 | 0 | -6 | 5 | |||
| 50 | 80 | 1.9685 | 3.1496 | 0 | -7 | 5 | |||
| 80 | 120 | 3.1496 | 4.7244 | 0 | -8 | 6 | |||
| 120 | 150 | 4.7244 | 5.9055 | 0 | -9 | 7 | |||
| 150 | 180 | 5.9055 | 7.0866 | 0 | -10 | 8 | |||
| 180 | 250 | 7.0866 | 9.8425 | 0 | -11 | 10 | |||
| 250 | 315 | 9.8425 | 12.4016 | 0 | -13 | 11 | |||
| 315 | 400 | 12.4016 | 15.7480 | 0 | -15 | 13 | |||
The key to determining the bearing tolerance class lies in the specification of the shaft's rotation accuracy at the support point.
Inner Ring Of P2, ABEC-9 Grade Tolerance (ISO Class 2)
| Bore Diameter (d) | Bore Tolerance (Δdmp) |
Radial Runout (Kia) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 0.6 | 2.5 | 0.0236 | 0.0984 | 0 | -2.5 | 1.5 | 0 | -40 | -250 |
| 2.5 | 10 | 0.0984 | 0.3937 | 0 | -2.5 | 1.5 | 0 | -40 | -250 |
| 10 | 18 | 0.3937 | 0.7087 | 0 | -2.5 | 1.5 | 0 | -80 | -250 |
| 18 | 30 | 0.7087 | 1.1811 | 0 | -2.5 | 2.5 | 0 | -120 | -250 |
| 30 | 50 | 1.1811 | 1.9685 | 0 | -2.5 | 2.5 | 0 | -120 | -250 |
| 50 | 80 | 1.9685 | 3.1496 | 0 | -4 | 2.5 | 0 | -150 | -250 |
| 80 | 120 | 3.1496 | 4.7244 | 0 | -5 | 2.5 | 0 | -200 | -380 |
| 120 | 150 | 4.7244 | 5.9055 | 0 | -7 | 2.5 | 0 | -250 | -380 |
| 150 | 180 | 5.9055 | 7.0866 | 0 | -7 | 5 | 0 | -250 | -380 |
| 180 | 250 | 7.0866 | 9.8425 | 0 | -8 | 5 | 0 | -300 | -500 |
Outer Ring Of P2, ABEC-9 Grade Tolerance (ISO Class 2)
| Outer Diameter (D) | Outer Dia. Tolerance (Δdmp) |
Radial Runout (Kea) | Width Tolerance (ΔBS) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| mm | inch | all | single bearing | paired bearings | |||||
| over | incl. | over | incl. | high | low | max. | high | low | |
| 2.5 | 6 | 0.0984 | 0.2362 | 0 | -2.5 | 1.5 | Identical to Width Tolerance (ΔBS) of Inner Ring of the same Bearing | ||
| 6 | 18 | 0.2362 | 0.7087 | 0 | -2.5 | 1.5 | |||
| 18 | 30 | 0.7087 | 1.1811 | 0 | -4 | 2.5 | |||
| 30 | 50 | 1.1811 | 1.9685 | 0 | -4 | 2.5 | |||
| 50 | 80 | 1.9685 | 3.1496 | 0 | -4 | 4 | |||
| 80 | 120 | 3.1496 | 4.7244 | 0 | -5 | 5 | |||
| 120 | 150 | 4.7244 | 5.9055 | 0 | -5 | 5 | |||
| 150 | 180 | 5.9055 | 7.0866 | 0 | -7 | 5 | |||
| 180 | 250 | 7.0866 | 9.8425 | 0 | -8 | 7 | |||
| 250 | 315 | 9.8425 | 12.4016 | 0 | -8 | 7 | |||
| 315 | 400 | 12.4016 | 15.7480 | 0 | -10 | 8 | |||
The key to determining the bearing tolerance class lies in the specification of the shaft's rotation accuracy at the support point.
Please provide your question. We’ll find you with the best support options.