Technical Guide · 6 min read
Bearing Cross-Reference Guide
How to find equivalent bearings across manufacturers. Covers exact replacements, dimensional matches, and common pitfalls.
What Is a Cross-Reference?
A bearing cross-reference identifies equivalent bearings from different manufacturers. Since most bearings follow ISO dimensional standards, a 6205 from SKF has the same bore (25mm), outer diameter (52mm), and width (15mm) as a 6205 from NSK, FAG, NTN, or KOYO.
There are three levels of equivalence:
Exact replacement — Same dimensions, same type, same internal design. Direct drop-in substitution.
Dimensional match — Same external dimensions but potentially different internal design details (cage type, clearance class, seal material).
Functional equivalent — Different dimensions but serves the same function in a specific application.
The Standard Number System
The ISO 15 standard means that most manufacturers use the same base designation:
| Base Number | All Manufacturers |
|---|---|
| 6205 | SKF 6205, NSK 6205, FAG 6205, NTN 6205, KOYO 6205 |
| 6308 | SKF 6308, NSK 6308, FAG 6308, NTN 6308, KOYO 6308 |
| 7206 | SKF 7206, NSK 7206, FAG 7206, NTN 7206, KOYO 7206 |
The base number is universal. What differs is the suffix convention for seals, clearance, and cage type. Timken uses a different system for some types — for example, their 200K is equivalent to a 6200 deep groove bearing.
Common Pitfalls
When cross-referencing, watch for these traps:
1. Suffix confusion. A SKF 6205-2RS1 and NSK 6205DDU are both sealed deep groove bearings, but the seal material and contact pressure may differ slightly. For most applications this doesn't matter, but for high-speed or extreme-temperature use, check the datasheet.
2. Load rating differences. Even with identical dimensions, manufacturers may rate bearings differently. A SKF 6205 has a dynamic load rating of 14.8 kN; the NSK version might be rated at 14.0 kN. The physical capability is similar, but the published numbers reflect different testing methodologies.
3. Precision grades. Standard industrial bearings (ABEC-1) are interchangeable across brands. Precision bearings (ABEC-5, ABEC-7) should generally be replaced with the same brand or verified for tolerance compatibility.
4. Obsolete numbers. Some older part numbers have been superseded. Always verify the current designation with the manufacturer.
How to Use BearingBrain for Cross-References
Enter any bearing part number in the search bar or chat. BearingBrain will:
1. Identify the bearing and its manufacturer
2. Look up all known equivalents from other brands
3. Show dimensional verification (bore, OD, width must match)
4. Display pricing from multiple suppliers
For brand-to-brand interchange tables, visit the Cross-Reference section where you can view complete conversion charts between any two manufacturers.