MAC / OUI Vendor Lookup & Format Converter
Normalize a MAC address, extract its OUI and look up the vendor locally in an imported CSV registry.
No MAC address is sent to a third party: formatting is local and vendor lookup runs against the CSV loaded in your browser.
Use the tool
Colon format
—Hyphen format
—Cisco format
—Plain hexadecimal
—OUI
—Vendor
—Import an IEEE OUI CSV file locally for manufacturer lookup. The file and MAC address stay in this browser session.
Use the result with confidence
Recommended workflow
- Enter only the technical identifier required for looking up a MAC-address vendor.
- Run the lookup and distinguish observed facts from interpretation.
- Cross-check warnings with configuration, logs or a second source before acting.
What to verify
- An OUI identifies an assigned organisation, not an exact hardware model.
- Randomised or locally administered MAC addresses may not identify the physical manufacturer.
- Use a current registry if vendor attribution matters to an inventory or investigation.
Questions about this tool
Does an OUI identify the exact device model?
No. It identifies the organisation assigned the prefix; vendors can use one prefix across many products.
Why can a MAC vendor lookup be misleading?
Locally administered or randomised MAC addresses may not correspond to the hardware manufacturer.
Can a MAC address identify a person?
Treat it as potentially identifying technical data in logs, but it does not reliably prove the identity of a person or device owner.