Reverse size lookup
Find a Ball Bearing by Size or Number
Search an exact base designation or enter one to three measured dimensions. More measurements produce a more meaningful match.
Default example: 6204 = 20 × 47 × 14 mm. A dimensional match is a candidate size—not proof that two bearings are interchangeable.
Dimension reference
Ball Bearing d, D, and B Dimensions
The selected bearing updates this diagram. Geometry is diagrammatic and not a manufacturing drawing or full-size template.
- Selected bearing
- 6204
- Bore diameter, d
- 20 mm
- Outside diameter, D
- 47 mm
- Width, B
- 14 mm
- Series
- 62
Common metric reference
Common Metric Ball Bearing Sizes
A deliberately bounded reference for common single-row deep-groove base designations. Sort or filter without leaving the page.
Search a bearing number or dimension string such as “6204” or “20 47 14”. Use View to send a row to the result and diagram.
No matching bearing appears in this limited common-series reference. Adjust the filters or verify the dimensions in the current manufacturer catalog; do not infer an unlisted size.
Scroll horizontally to view additional columns and vertically to view additional rows. Column headers remain visible while scrolling.
| Boundary dimensions | Size d × D × B | Actions | |||||
|---|---|---|---|---|---|---|---|
| 6000 | 60 | 00 | 10 mm | 26 mm | 8 mm | 10 × 26 × 8 mm | |
| 6001 | 60 | 01 | 12 mm | 28 mm | 8 mm | 12 × 28 × 8 mm | |
| 6002 | 60 | 02 | 15 mm | 32 mm | 9 mm | 15 × 32 × 9 mm | |
| 6003 | 60 | 03 | 17 mm | 35 mm | 10 mm | 17 × 35 × 10 mm | |
| 6004 | 60 | 04 | 20 mm | 42 mm | 12 mm | 20 × 42 × 12 mm | |
| 6005 | 60 | 05 | 25 mm | 47 mm | 12 mm | 25 × 47 × 12 mm | |
| 6006 | 60 | 06 | 30 mm | 55 mm | 13 mm | 30 × 55 × 13 mm | |
| 6200 | 62 | 00 | 10 mm | 30 mm | 9 mm | 10 × 30 × 9 mm | |
| 6201 | 62 | 01 | 12 mm | 32 mm | 10 mm | 12 × 32 × 10 mm | |
| 6202 | 62 | 02 | 15 mm | 35 mm | 11 mm | 15 × 35 × 11 mm | |
| 6203 | 62 | 03 | 17 mm | 40 mm | 12 mm | 17 × 40 × 12 mm | |
| 6204 | 62 | 04 | 20 mm | 47 mm | 14 mm | 20 × 47 × 14 mm | |
| 6205 | 62 | 05 | 25 mm | 52 mm | 15 mm | 25 × 52 × 15 mm | |
| 6206 | 62 | 06 | 30 mm | 62 mm | 16 mm | 30 × 62 × 16 mm | |
| 6300 | 63 | 00 | 10 mm | 35 mm | 11 mm | 10 × 35 × 11 mm | |
| 6301 | 63 | 01 | 12 mm | 37 mm | 12 mm | 12 × 37 × 12 mm | |
| 6302 | 63 | 02 | 15 mm | 42 mm | 13 mm | 15 × 42 × 13 mm | |
| 6303 | 63 | 03 | 17 mm | 47 mm | 14 mm | 17 × 47 × 14 mm | |
| 6304 | 63 | 04 | 20 mm | 52 mm | 15 mm | 20 × 52 × 15 mm | |
| 6305 | 63 | 05 | 25 mm | 62 mm | 17 mm | 25 × 62 × 17 mm | |
| 6306 | 63 | 06 | 30 mm | 72 mm | 19 mm | 30 × 72 × 19 mm | |
| 6800 | 68 | 00 | 10 mm | 19 mm | 5 mm | 10 × 19 × 5 mm | |
| 6801 | 68 | 01 | 12 mm | 21 mm | 5 mm | 12 × 21 × 5 mm | |
| 6802 | 68 | 02 | 15 mm | 24 mm | 5 mm | 15 × 24 × 5 mm | |
| 6803 | 68 | 03 | 17 mm | 26 mm | 5 mm | 17 × 26 × 5 mm | |
| 6804 | 68 | 04 | 20 mm | 32 mm | 7 mm | 20 × 32 × 7 mm | |
| 6805 | 68 | 05 | 25 mm | 37 mm | 7 mm | 25 × 37 × 7 mm | |
| 6806 | 68 | 06 | 30 mm | 42 mm | 7 mm | 30 × 42 × 7 mm | |
| 6900 | 69 | 00 | 10 mm | 22 mm | 6 mm | 10 × 22 × 6 mm | |
| 6901 | 69 | 01 | 12 mm | 24 mm | 6 mm | 12 × 24 × 6 mm | |
| 6902 | 69 | 02 | 15 mm | 28 mm | 7 mm | 15 × 28 × 7 mm | |
| 6903 | 69 | 03 | 17 mm | 30 mm | 7 mm | 17 × 30 × 7 mm | |
| 6904 | 69 | 04 | 20 mm | 37 mm | 9 mm | 20 × 37 × 9 mm | |
| 6905 | 69 | 05 | 25 mm | 42 mm | 9 mm | 25 × 42 × 9 mm | |
| 6906 | 69 | 06 | 30 mm | 47 mm | 9 mm | 30 × 47 × 9 mm | |
Nominal boundary dimensions only. Verify the exact manufacturer designation, bearing type, suffix, internal clearance, seals or shields, precision/tolerance class, ratings, fits, lubrication, and service conditions before specification or replacement.
More filters and actions
How to Read Ball Bearing Dimensions
Ball bearing boundary dimensions are normally written d × D × B. Lowercase d is the bore diameter that fits over the shaft, uppercase D is the outside diameter that fits in the housing, and B is the axial width of the bearing.
- d — bore diameter
- The inside diameter through the inner ring.
- D — outside diameter
- The largest outside diameter of the outer ring.
- B — width
- The bearing’s axial boundary width.
Example: 6204
6204 = 20 × 47 × 14 mm: 20 mm bore, 47 mm outside diameter, and 14 mm width. Those dimensions identify the base size; they do not by themselves establish seals, clearance, tolerance class, load capacity, or application suitability.
How Ball Bearing Numbers Relate to Bore Size
For common standardized bearing designations, the final two-digit bore code gives useful information about the nominal bore. The special codes 00, 01, 02, and 03 correspond to 10, 12, 15, and 17 mm. From code 04 upward in the applicable common range, multiplying the code by 5 gives the nominal bore in millimeters.
| Bore code | Nominal bore | Example designation |
|---|---|---|
| 00 | 10 mm | 6200 |
| 01 | 12 mm | 6201 |
| 02 | 15 mm | 6202 |
| 03 | 17 mm | 6203 |
| 04 | 20 mm | 6204 |
| 06 | 30 mm | 6206 |
Do not use this shortcut to decode manufacturer suffixes, seals, shields, precision classes, internal clearances, snap-ring variants, or special/nonstandard bore designs.
6000 vs 6200 vs 6300 vs 6800 vs 6900 Series
The same bore diameter can appear in several dimensional series. That is why measuring only the shaft/bore is not enough to identify a replacement bearing.
| Bearing | Series | d × D × B | What changes |
|---|---|---|---|
| 6800 | 68 | 10 × 19 × 5 mm | Very compact boundary envelope |
| 6900 | 69 | 10 × 22 × 6 mm | Larger OD and width than 6800 |
| 6000 | 60 | 10 × 26 × 8 mm | Larger envelope again |
| 6200 | 62 | 10 × 30 × 9 mm | Still larger OD and width |
| 6300 | 63 | 10 × 35 × 11 mm | Largest envelope in this comparison |
This dimensional comparison should not be converted into a blanket load-capacity ranking. Actual ratings, speed limits, cage, clearance, lubrication, and suffix details must be checked for the exact bearing.
How to Measure a Ball Bearing for Replacement
- Read the designation first. Clean the ring and look for an etched or stamped base number and suffixes.
- Measure the bore. Use calipers or a micrometer across clean, undamaged inner-ring surfaces.
- Measure the outside diameter. Measure across the outer ring at more than one orientation if wear or damage is suspected.
- Measure the width. Measure the axial distance across the bearing faces without including removable external hardware.
- Compare all three dimensions. Enter d, D, and B above; using all three reduces ambiguous matches.
Field measurements help identify a candidate size. They are not a substitute for the manufacturer’s dimensional tolerances or a calibrated inspection process.
Why Matching Size Does Not Prove Interchangeability
Replacement warning
A bearing that fits the same shaft and housing can still be wrong for the machine. Confirm the complete designation and application requirements before replacement.
Bearing type
Deep-groove, angular-contact, self-aligning, roller, and thrust bearings can use very different internal geometries.
Suffixes and clearance
Seals, shields, snap-ring features, internal clearance, precision, and other suffix meanings are manufacturer-specific.
Performance
Dynamic/static load ratings, limiting speeds, lubrication, temperature capability, and life must suit the application.
Fits and mounting
Shaft and housing fits, shoulders, fillets, preload/endplay, and mounting method remain part of the engineering design.
Standards, Dataset Scope, and Source Method
Dataset T2E-BB-DIM-1 · 35 common metric single-row deep-groove base sizes · 60/62/63/68/69 series · 10, 12, 15, 17, 20, 25, and 30 mm bores · canonical units: millimeters.
ISO 15:2017 provides the standardization context for radial-bearing boundary dimensions. Turn2Engineering does not reproduce the ISO standard or a complete manufacturer catalog. The table above is a bounded, reorganized dimensional reference checked against current official manufacturer material; manufacturer performance fields are intentionally excluded.
- ISO 15:2017 — Rolling bearings — Radial bearings — Boundary dimensionsUsed for standardization context and terminology; ISO publications remain copyrighted.
- NSK — Single-Row Deep Groove Ball BearingsOfficial manufacturer reference used to verify base-designation boundary dimensions and series scope.
- SKF — Standardized Boundary DimensionsIndependent manufacturer reference for boundary-dimension standardization.
- Schaeffler — Bearing DataIndependent reference for common bearing bore-code interpretation.
Dataset and Source-Check Details
- Publisher
- Turn2Engineering
- Source checked
- August 16, 2026
- Standard context
- ISO 15:2017
- Included fields
- Base designation, series, bore code, d, D, B
- Canonical units
- Millimeters; inch values are calculated as mm ÷ 25.4
- Excluded fields
- Loads, speeds, mass, cage, lubrication, clearances, suffix catalogs
- Rights decision
- Limited transformed reference; no full catalog/standard reproduction
- Download decision
- Full CSV disabled pending separate rights review
Ball Bearing Size Chart FAQ
They are normally written d × D × B: bore diameter, outside diameter, and bearing width.
The base 6204 reference used here is 20 mm bore × 47 mm outside diameter × 14 mm width; verify the complete suffix and application requirements before replacement.
Yes; different dimensional series can share the same bore while using different outside diameters and widths.
Common seal or shield variants often retain the same basic d, D, and B envelope, but suffix meanings and product details are manufacturer-specific and must be checked in the exact catalog.
Dimensions can narrow the candidate designation, but final replacement also requires matching bearing type, suffix/specification, clearance, ratings, fits, speed, lubrication, and service conditions.
Identify the Size, Then Verify the Bearing
Use the chart and reverse lookup to identify a likely base size from the bearing number or measured d × D × B dimensions. Then verify the full designation and application requirements with the exact manufacturer’s current product data before purchasing or specifying the bearing.
- Continue to bearing selection
Check load, life, speed, lubrication, fits, clearance, environment, and mounting requirements.