How to Find the Information That Affects Your Catalytic Converter’s Value
Correct VIN details and catalytic converter serial numbers help us identify your converter faster and price it more accurately.
This guide explains what matters, where to look, and what to do if information is missing.
What Is a VIN (Vehicle Identification Number)?
A VIN is a 17-character code assigned to every vehicle by the manufacturer. It identifies:
- Make & model
- Engine type
- Year of manufacture
- Country of origin
While the VIN itself is not always required, it can help narrow down which catalytic converters were originally installed on a vehicle.
Where to Find the VIN on a Vehicle
Common VIN locations include:
- Driver-side dashboard (visible through the windshield)
- Driver-side door jamb sticker
- Vehicle registration or title
- Insurance documents
Tip: If the converter is already removed, the VIN is optional — photos are usually enough
Do Catalytic Converters Have VIN Numbers?
No. Catalytic converters do not contain full VINs.
Instead, OEM catalytic converters usually have:
- Stamped serial numbers
- Manufacturer codes
- Letters, symbols, or partial identifiers
These markings are what matter most for pricing.
How to Find a Serial Number or Stamped Code
Look on the outer shell of the catalytic converter for:
- Letters and numbers stamped into the metal
- Partial codes (not a full VIN)
- Manufacturer logos or symbols
Serial numbers may be:
- On the side of the converter body
- Near the inlet or outlet pipe
- Faint, worn, or partially rusted
Even incomplete or hard-to-read markings are useful.
OEM vs Aftermarket: Why Serial Numbers Matter
OEM (Original Equipment Manufacturer)
- Installed by the vehicle manufacturer
- Usually stamped with identifiable codes
- Typically higher precious metal content
- Higher resale value in most cases
Aftermarket
- Replacement parts
- Often fewer or no serial markings
- Metal content varies widely
- Typically lower value
Rule of thumb:
Clear stamps = more likely OEM
Blank or generic casing = often aftermarket
What If There’s No Serial Number?
That’s okay.
Many legitimate converters:
- Have worn or rusted stamps
- Are aftermarket and unmarked
- Have heat shields covering markings
In these cases, photos + size + shape are enough for identification.
Best Photos to Send for Identification
Photos are the fastest way to identify a converter accurately.
Please include:
- Full converter (entire unit)
- Close-ups of any stamps or markings
- Side angles showing shape and size
- Interior view (only if already cut open)
Phone photos are perfectly fine.
Important Safety Note
Do not cut open a catalytic converter just to look for numbers.
Only photograph the interior if it is already opened.