Bearing Size Calculator
Pick the bearing series, enter the two-digit bore code from the bearing number and choose the seal type. The calculator returns the full bearing number with its bore, outer diameter and width.
- 6000, 6200 and 6300 series
- Millimetres and inches
- Seal and shield codes
Covers bore codes 00 to 20, which is a 10 to 100 mm shaft. Larger and metric-inch bearings use other tables.
A bearing number is a size code, not a part number. In a 6205 bearing, the 6 means a deep groove ball bearing, the 2 is the light series and 05 is the bore code. Multiply codes from 04 upwards by 5 to get the bore in millimetres, so 05 is a 25 mm shaft. Any maker's 6205 has the same dimensions.
Bearing size chart
Popular deep groove ball bearings. Search by number or dimension.
| Bore code | Bore | 60 series | 62 series | 63 series |
|---|---|---|---|---|
| 00 | 10 | 26 × 8 | 30 × 9 | 35 × 11 |
| 01 | 12 | 28 × 8 | 32 × 10 | 37 × 12 |
| 02 | 15 | 32 × 9 | 35 × 11 | 42 × 13 |
| 03 | 17 | 35 × 10 | 40 × 12 | 47 × 14 |
| 04 | 20 | 42 × 12 | 47 × 14 | 52 × 15 |
| 05 | 25 | 47 × 12 | 52 × 15 | 62 × 17 |
| 06 | 30 | 55 × 13 | 62 × 16 | 72 × 19 |
| 07 | 35 | 62 × 14 | 72 × 17 | 80 × 21 |
| 08 | 40 | 68 × 15 | 80 × 18 | 90 × 23 |
| 10 | 50 | 80 × 16 | 90 × 20 | 110 × 27 |
| 12 | 60 | 95 × 18 | 110 × 22 | 130 × 31 |
| 15 | 75 | 115 × 20 | 130 × 25 | 160 × 37 |
| 20 | 100 | 150 × 24 | 180 × 34 | 215 × 47 |
Bore codes 00 to 03 are special: 10, 12, 15 and 17 mm. From 04 upwards, bore = code × 5.
One shaft, three series
Same bore, different housings. Slide the bore code.
Heavier series have larger balls, which carry more load but need a bigger housing. If space allows, a 63 series bearing lasts longer under heavy or shock loads.
How to read a bearing number
Every digit has a meaning. Step through 6205-2RS.
Type
6 means a single row deep groove ball bearing.
Extra letters after the number, such as C3 for extra internal clearance, do not change the size. They matter for speed and heat, so match them when replacing a bearing.
Open, ZZ or 2RS
Seal type changes where a bearing works best. Compare the three options.
No seals. Lubricated by oil or grease from the machine.
Metal shields with a small gap. Holds grease in, keeps large dirt out.
Rubber seals that touch the inner ring. Keeps out water and fine dust.
Rubber seals keep out water and dust best but add a little drag. Metal shields suit clean, fast machinery like electric motors.
Replacing a bearing
Match more than the size. Tick each point.
Tick each item as you go.
Press a new bearing on by the ring that is the tight fit. Pressing through the balls damages the raceways before the bearing has turned once.
What you get
Every dimension of the bearing. Each tile explains one result.
The full designation with seal code.
Shaft diameter in mm and inches.
Housing bore in mm and inches.
Bearing thickness.
Open, shielded or sealed.
Imperial conversions help when replacing bearings on older American equipment, though true inch bearings use different numbers such as R8 or 1640.
Frequently Asked Questions
No question matches that search.
What size is a 6205 bearing?
25 mm bore, 52 mm outer diameter and 15 mm wide.
How do I work out bearing bore size?
For codes 04 and above, multiply the last two digits by 5. 6208 has a 40 mm bore.
What size is a 6203 bearing?
17 mm bore, 40 mm outer diameter and 12 mm wide. Codes 00 to 03 do not follow the × 5 rule.
What is the difference between 2RS and ZZ?
2RS has rubber seals that touch the inner ring. ZZ has metal shields with a small gap.
Is a 6205 the same from every brand?
Yes, the dimensions are set by ISO 15. Quality, clearance and grease vary.
What does C3 mean on a bearing?
Extra internal clearance, used where the bearing runs hot or has a tight fit.
What is the difference between 6000 and 6200 series?
The same bore, but the 6200 is larger outside and wider, so it carries more load.
Find the right bearing fast
Read the series and bore code from the old bearing, choose the seal type and the calculator gives the exact dimensions. Match the clearance class too, and the replacement will fit and run just like the original.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.