# MAC Address Vendor Lookup (IEEE OUI Registry)

> MAC Address Vendor Lookup (IEEE OUI Registry) is a paid API for AI agents from api.companyrecords-api.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Returns the registered hardware vendor name for a given MAC address or OUI prefix by querying the IEEE OUI registry via macvendors.com.

## Facts

- Endpoint: GET https://api.companyrecords-api.workers.dev/api/b2b/macvendors-lookup?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mac-address-vendor-lookup-ieee-oui-registry-2f5f6c74
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Y4AmOLqS1mqBwFipG_ipL

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability mac-address-vendor-lookup-ieee-oui-registry-2f5f6c74
```

Example prompt: What company manufactured the device with MAC address 44:38:39:ff:ef:57? Look up the registered vendor from the IEEE OUI registry.

## When to prefer this

Use this endpoint when you need to quickly identify the hardware manufacturer of a device given its MAC address or OUI prefix, especially for network inventory, security auditing, or device identification tasks. It is ideal when you want a simple vendor name lookup without needing full device profile data. Prefer this over manual IEEE registry lookups or building your own OUI database.

## Known failure modes

- Unknown or unregistered OUI returns an error or empty vendor field if the MAC prefix is not in the IEEE registry
- Malformed MAC address input (wrong format, wrong length) may return a 400-level error
- Rate limiting or upstream macvendors.com availability issues could cause failures
- Private/locally administered MAC addresses (second bit of first byte set) are not registered and will not resolve to a vendor

## How this service works

Pay-per-call company registry, government, legal and B2B data tools for AI agents, from official registers and public sources. Payment: x402, USDC on Base, Solana, Arc, Polygon, Arbitrum, Monad, World Chain, Optimism, Avalanche, Celo or Stellar, or RLUSD/XRP on the XRP Ledger. No signup, no API key; a failed call is not charged.

## Output

A JSON object containing the full MAC address queried, the OUI prefix (first three octets), the registered vendor name (e.g. 'Cumulus Networks, inc'), the source URL (macvendors.com API), and a checkedAt timestamp indicating when the lookup was performed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "mac"
     ],
     "properties": {
      "mac": {
       "type": "string",
       "description": "MAC address or OUI, e.g. 44:38:39:ff:ef:57 or 443839"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "mac": "44:38:39:ff:ef:57",
  "oui": "44:38:39",
  "source": "https://api.macvendors.com/",
  "vendor": "Cumulus Networks, inc",
  "checkedAt": "2026-10-23T09:37:36.959Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mac-address-vendor-lookup-ieee-oui-registry-2f5f6c74/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.companyrecords-api.workers.dev](https://www.zero.xyz/host/api.companyrecords-api.workers.dev/llms.txt)