GET/api/v2/mac

MAC lookup API

The vendor behind a MAC address or prefix, its IEEE block, and what the address itself says (randomized, multicast, virtual).

120 calls a minute per IP
Same engine as the MAC Lookup tool

200 OKRecorded 2026-10-25. Send it to run the request live.

{
  "query": {
    "address": "B8:27:EB:12:34:56"
  },
  "address": "B8:27:EB:12:34:56",
  "prefix": null,
  "kind": "vendor",
  "vendor": {
    "name": "Raspberry Pi Foundation",
    "address": "Mitchell Wood House Caldecote Cambridgeshire US CB23 7NU",
    "country": "GB",
    "countryName": "United Kingdom",
    "location": {
      "place": "Cambridge, England",
      "latitude": 52.195,
      "longitude": -0.029,
      "precision": "postal"
    }
  },
  "assignment": {
    "prefix": "B8:27:EB",
    "block": "MA-L",
    "size": 16777216,
    "firstAddress": "B8:27:EB:00:00:00",
    "lastAddress": "B8:27:EB:FF:FF:FF",
    "organization": "Raspberry Pi Foundation",
    "firstSeen": null,
    "firstListed": {
      "on": "2012-03-02",
      "notOn": "2012-02-04"
    },
    "nameHistory": null
  },
  "flags": {
    "multicast": false,
    "locallyAdministered": false,
    "broadcast": false
  },
  "localQuadrant": null,
  "likelyRandomized": false,
  "special": null,
  "ipv6": {
    "interfaceId": "ba27:ebff:fe12:3456",
    "linkLocal": "fe80::ba27:ebff:fe12:3456",
    "solicitedNode": "ff02::1:ff12:3456",
    "solicitedNodeMac": "33:33:ff:12:34:56"
  },
  "formats": {
    "colon": "b8:27:eb:12:34:56",
    "dash": "B8-27-EB-12-34-56",
    "dot": "b827.eb12.3456",
    "bare": "B827EB123456"
  },
  "source": {
    "registry": "IEEE Registration Authority",
    "updated": "2026-10-18",
    "url": "https://standards-oui.ieee.org/"
  },
  "tookMs": 440
}

Jump to a section

How it works

Looks the address up in the IEEE Registration Authority's public listing (MA-L, MA-M, MA-S, IAB and CID blocks, the most specific first) and reads its own bits: the multicast (I/G) and locally administered (U/L) flags, IEEE 802c's local quadrant, and well-known special addresses (broadcast, IPv4 and IPv6 multicast mappings, STP and LLDP, VRRP and HSRP virtual routers, VMware, VirtualBox, Hyper-V, Docker and QEMU defaults).

A locally administered unicast address in no registry is almost always randomized (iOS, Android and Windows do it per network): likelyRandomized says so, and no vendor can be known. Organizations that paid the IEEE to stay unlisted come back as kind: "private".

Send a full address in any notation, or just its first 6 to 11 hex digits (then address is null and prefix is set). ipv6 is the modified EUI-64 interface ID and link-local address a host could build from it.

Answers kept: 1 day (`public, max-age=86400`): the registry snapshot changes with our monthly sync.

Query parameters

addressstringrequired
A MAC address in any notation (B8:27:EB:12:34:56, b8-27-eb-12-34-56, b827.eb12.3456) or its first 6 to 11 hex digits.

Response fields

200 with this JSON object, plus tookMs, and incomplete with warnings when a source failed. Fields marked optional appear only when they apply.

queryobjectalways
What was looked up, normalised (lower case, no trailing dot, IDNs as Punycode).
- addressstringalways
  The address (or prefix) in upper-case colon notation.
addressstring or nullalways
The full address, colon notation; null when a prefix was sent.
prefixstring or nullalways
The prefix sent, when it wasn't a full address.
kindstringalways
vendor (a company holds the block), private (unlisted at the holder's request), block (an IEEE block split into MA-M/MA-S, unassigned here), cid (a Company ID, IEEE 802c), local (locally administered, in no registry), unlisted, multicast, broadcast.
one of "vendor", "private", "block", "cid", "local", "unlisted", "multicast", "broadcast"
vendorobject or nullalways
The organization holding the block; null for private, local, unlisted and CID addresses. For a multicast address, the protocol's owner.
Show 5 fields
- namestringalways
  The organization as registered.
- addressstring or nullalways
  Its registered postal address.
- countrystring or nullalways
  ISO 3166-1 alpha-2 code where it is.
- countryNamestring or nullalways
  The country's English name.
- locationobject or nullalways
  Where the registered address is (GeoNames), or null.
  Show 4 fields
  - placestringalways
    The place's name.
  - latitudenumberalways
    Latitude.
  - longitudenumberalways
    Longitude.
  - precisionstringalways
    How precisely it could be placed: postal, city or country.
    one of "postal", "city", "country"
assignmentobject or nullalways
The registry entry that covers the address, or null.
Show 9 fields
- prefixstringalways
  The assigned prefix, colon notation.
- blockstringalways
  MA-L (24 bits), MA-M (28), MA-S (36), IAB (36) or CID (24).
  one of "MA-L", "MA-M", "MA-S", "IAB", "CID"
- sizeintegeralways
  How many addresses the block holds.
- firstAddressstringalways
  Its first address.
- lastAddressstringalways
  Its last address.
- organizationstringalways
  The organization as registered (also for private and CID entries).
- firstSeenstring or nullalways
  When our monthly sync first saw it listed (YYYY-MM-DD); null for entries older than our first sync.
- firstListedobject or nullalways
  From archived copies of the IEEE's listing (the Wayback Machine): the first copy that lists it, and the last earlier one that didn't. The assignment falls between them.
  Show 2 fields
  - onstringalways
    First copy listing it (YYYY-MM-DD).
  - notOnstring or nullalways
    Last earlier copy without it; null when the earliest copy already lists it.
- nameHistoryarray of objects or nullalways
  Earlier holder names, when the name changed (an acquisition), the current one last; null when it never changed.
  Show 2 fields
  - namestringalways
    The holder's name.
  - sincestringalways
    The archived copy it first appears in (YYYY-MM-DD).
flagsobjectalways
The first octet's two flag bits.
- multicastbooleanalways
  I/G bit: a group (multicast) address.
- locallyAdministeredbooleanalways
  U/L bit: set locally (randomized, virtual or by hand), not by the vendor.
- broadcastbooleanalways
  FF:FF:FF:FF:FF:FF.
localQuadrantstring or nullalways
IEEE 802c's quadrant of a local unicast address: aai (administratively assigned: random or by hand), eli (extended local, under a CID), sai (standard assigned), reserved; null otherwise.
one of "aai", "eli", "sai", "reserved", null
likelyRandomizedboolean or nullalways
A locally administered unicast address in no registry (or Android's 02:00:00:00:00:00): almost always a randomized, private address. Null under a Company ID, whose holder may hand out random addresses too.
specialobject or nullalways
What the address means beyond its registry entry, or null.
Show 4 fields
- idstringalways
  e.g. broadcast, ipv4-multicast, ipv6-multicast, ipv6-solicited, stp, lldp, vrrp4, hsrp1, vmware, virtualbox, hyperv, docker, qemu, android.
- groupstringalways
  group, protocol, router or virtual.
  one of "group", "protocol", "router", "virtual"
- valuesobjectalways
  Values the address carries, e.g. group (the IP multicast group), number (the virtual router's).
- servicestring or nullalways
  A multicast group's well-known service, e.g. mdns, allNodes.
ipv6object or nullalways
What an IPv6 host using this address with modified EUI-64 would take (unicast addresses only), or null.
Show 4 fields
- interfaceIdstringalways
  The interface ID.
- linkLocalstringalways
  The link-local address.
- solicitedNodestringalways
  That address's solicited-node multicast group.
- solicitedNodeMacstringalways
  The MAC address that group is sent to.
formatsobject or nullalways
The full address in each system's notation, or null for a prefix.
Show 4 fields
- colonstringalways
  Linux, macOS: lower case, colons.
- dashstringalways
  Windows: upper case, dashes.
- dotstringalways
  Cisco: three groups of four.
- barestringalways
  12 hex digits, upper case.
sourceobjectalways
The registry snapshot.
- registrystringalways
  Always IEEE Registration Authority.
- updatedstringalways
  When our copy was synced (YYYY-MM-DD).
- urlstringalways
  The IEEE's public listing.

Errors

503 unavailable The registry files couldn't be read.

Plus the errors every endpoint can return: 400 for a missing or unreadable parameter, 429 past the limit, 503 when every source failed.

curl "https://dnsrobot.net/api/v2/mac?address=B8%3A27%3AEB%3A12%3A34%3A56"

const params = new URLSearchParams({ address: "B8:27:EB:12:34:56" });
const res = await fetch(`https://dnsrobot.net/api/v2/mac?${params}`);
const data = await res.json();
if (!res.ok) throw new Error(data.error.message);
console.log(data.vendor);

import requests

r = requests.get(
    "https://dnsrobot.net/api/v2/mac",
    params={"address": "B8:27:EB:12:34:56"},
    timeout=30,
)
data = r.json()
if not r.ok:
    raise RuntimeError(data["error"]["message"])
print(data["vendor"])

package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
)

func main() {
	q := url.Values{"address": {"B8:27:EB:12:34:56"}}
	res, err := http.Get("https://dnsrobot.net/api/v2/mac?" + q.Encode())
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()
	var data map[string]any
	if err := json.NewDecoder(res.Body).Decode(&data); err != nil {
		panic(err)
	}
	if res.StatusCode != http.StatusOK {
		panic(data["error"])
	}
	fmt.Println(data["vendor"])
}

<?php
$query = http_build_query(["address" => "B8:27:EB:12:34:56"]);
$context = stream_context_create(["http" => ["ignore_errors" => true, "timeout" => 30]]);
$data = json_decode(file_get_contents("https://dnsrobot.net/api/v2/mac?" . $query, false, $context), true);
if (isset($data["error"])) {
    throw new RuntimeException($data["error"]["message"]);
}
print_r($data["vendor"]);

require "net/http"
require "json"

uri = URI("https://dnsrobot.net/api/v2/mac")
uri.query = URI.encode_www_form(address: "B8:27:EB:12:34:56")
data = JSON.parse(Net::HTTP.get(uri))
raise data["error"]["message"] if data["error"]
puts data["vendor"]

// Cargo.toml: reqwest = { version = "0.13", features = ["blocking", "json"] }, serde_json = "1"
fn main() -> Result<(), Box<dyn std::error::Error>> {
    let res = reqwest::blocking::get("https://dnsrobot.net/api/v2/mac?address=B8%3A27%3AEB%3A12%3A34%3A56")?;
    let ok = res.status().is_success();
    let data: serde_json::Value = res.json()?;
    if !ok {
        return Err(data["error"]["message"].to_string().into());
    }
    println!("{}", data["vendor"]);
    Ok(())
}

using System.Text.Json;

using var http = new HttpClient();
var res = await http.GetAsync("https://dnsrobot.net/api/v2/mac?address=B8%3A27%3AEB%3A12%3A34%3A56");
var data = JsonDocument.Parse(await res.Content.ReadAsStringAsync()).RootElement;
if (!res.IsSuccessStatusCode)
    throw new Exception(data.GetProperty("error").GetProperty("message").GetString());
Console.WriteLine(data.GetProperty("vendor"));

A Raspberry Pi

GET /api/v2/mac?address=B8%3A27%3AEB%3A12%3A34%3A56

200 OKRecorded 2026-10-25

{
  "query": {
    "address": "B8:27:EB:12:34:56"
  },
  "address": "B8:27:EB:12:34:56",
  "prefix": null,
  "kind": "vendor",
  "vendor": {
    "name": "Raspberry Pi Foundation",
    "address": "Mitchell Wood House Caldecote Cambridgeshire US CB23 7NU",
    "country": "GB",
    "countryName": "United Kingdom",
    "location": {
      "place": "Cambridge, England",
      "latitude": 52.195,
      "longitude": -0.029,
      "precision": "postal"
    }
  },
  "assignment": {
    "prefix": "B8:27:EB",
    "block": "MA-L",
    "size": 16777216,
    "firstAddress": "B8:27:EB:00:00:00",
    "lastAddress": "B8:27:EB:FF:FF:FF",
    "organization": "Raspberry Pi Foundation",
    "firstSeen": null,
    "firstListed": {
      "on": "2012-03-02",
      "notOn": "2012-02-04"
    },
    "nameHistory": null
  },
  "flags": {
    "multicast": false,
    "locallyAdministered": false,
    "broadcast": false
  },
  "localQuadrant": null,
  "likelyRandomized": false,
  "special": null,
  "ipv6": {
    "interfaceId": "ba27:ebff:fe12:3456",
    "linkLocal": "fe80::ba27:ebff:fe12:3456",
    "solicitedNode": "ff02::1:ff12:3456",
    "solicitedNodeMac": "33:33:ff:12:34:56"
  },
  "formats": {
    "colon": "b8:27:eb:12:34:56",
    "dash": "B8-27-EB-12-34-56",
    "dot": "b827.eb12.3456",
    "bare": "B827EB123456"
  },
  "source": {
    "registry": "IEEE Registration Authority",
    "updated": "2026-10-18",
    "url": "https://standards-oui.ieee.org/"
  },
  "tookMs": 440
}

A randomized (private) address

GET /api/v2/mac?address=52%3A1C%3A9F%3A6B%3A2C%3A0E

200 OKRecorded 2026-10-25

{
  "query": {
    "address": "52:1C:9F:6B:2C:0E"
  },
  "address": "52:1C:9F:6B:2C:0E",
  "prefix": null,
  "kind": "local",
  "vendor": null,
  "assignment": null,
  "flags": {
    "multicast": false,
    "locallyAdministered": true,
    "broadcast": false
  },
  "localQuadrant": "aai",
  "likelyRandomized": true,
  "special": null,
  "ipv6": {
    "interfaceId": "501c:9fff:fe6b:2c0e",
    "linkLocal": "fe80::501c:9fff:fe6b:2c0e",
    "solicitedNode": "ff02::1:ff6b:2c0e",
    "solicitedNodeMac": "33:33:ff:6b:2c:0e"
  },
  "formats": {
    "colon": "52:1c:9f:6b:2c:0e",
    "dash": "52-1C-9F-6B-2C-0E",
    "dot": "521c.9f6b.2c0e",
    "bare": "521C9F6B2C0E"
  },
  "source": {
    "registry": "IEEE Registration Authority",
    "updated": "2026-10-18",
    "url": "https://standards-oui.ieee.org/"
  },
  "tookMs": 349
}

A vendor prefix only

GET /api/v2/mac?address=00%3A50%3A56

200 OKRecorded 2026-10-25

{
  "query": {
    "address": "00:50:56"
  },
  "address": null,
  "prefix": "00:50:56",
  "kind": "vendor",
  "vendor": {
    "name": "VMware, Inc.",
    "address": "3401 Hillview Avenue PALO ALTO CA US 94304",
    "country": "US",
    "countryName": "United States",
    "location": {
      "place": "Palo Alto, California",
      "latitude": 37.433,
      "longitude": -122.184,
      "precision": "postal"
    }
  },
  "assignment": {
    "prefix": "00:50:56",
    "block": "MA-L",
    "size": 16777216,
    "firstAddress": "00:50:56:00:00:00",
    "lastAddress": "00:50:56:FF:FF:FF",
    "organization": "VMware, Inc.",
    "firstSeen": null,
    "firstListed": {
      "on": "2000-11-09",
      "notOn": "1998-04-22"
    },
    "nameHistory": null
  },
  "flags": {
    "multicast": false,
    "locallyAdministered": false,
    "broadcast": false
  },
  "localQuadrant": null,
  "likelyRandomized": false,
  "special": {
    "id": "vmware",
    "group": "virtual",
    "values": {},
    "service": null
  },
  "ipv6": null,
  "formats": null,
  "source": {
    "registry": "IEEE Registration Authority",
    "updated": "2026-10-18",
    "url": "https://standards-oui.ieee.org/"
  },
  "tookMs": 295
}

MAC lookup API

How it works

Query parameters

Response fields

Errors

Code samples