MAC address formatter & EUI normalize

Client

Turn messy layer-2 strings into readable colon, hyphen, dotted, and plain hex variants for IEEE EUI-48 (six octets) or EUI-64 (eight octets). Shows standard group (multicast) and local admin bits from the first octet—all client-side. For IP math, open CIDR or IPv6 formatting.

Layer-2 identifiers — normalizes IEEE EUI-48 (6 octets) and EUI-64 (8 octets); not IP routing. Pair with CIDR or IPv6 expand & compress for addressing math.

MAC / EUI

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Accepted: colon or hyphen separators, spaced octets, plain 12 / 16 hex digits, or dotted groups (3×4 hex for 48-bit, 4×4 for 64-bit). Paste multiple lines — the first readable address wins.

EUI-48 (48-bit MAC) · Unicast (group bit clear) · Universal (vendor-assigned OUIs when unicast)

  • Colon (IEEE, lower)

    00:1a:2b:3c:4d:5e

  • Colon (upper)

    00:1A:2B:3C:4D:5E

  • Hyphen

    00-1a-2b-3c-4d-5e

  • Dotted groups

    001a.2b3c.4d5e

  • Plain hex (lower)

    001a2b3c4d5e

  • Plain hex (upper)

    001A2B3C4D5E

Common use cases

  • Match dhcpd, ARP tables, switch logs, and Wi‑Fi driver output by converting everything to one canonical lowercase colon form.
  • Paste vendor datasheets or stickers that mix dotted four-digit groups with tools that expect hyphens.
  • Quickly spot whether an address looks like a multicast listener or a locally administered STA before you chase OUI lookups.

Common mistakes to avoid

  • Expecting OUIs or vendor names

    This page formats bytes only. It does not call registries—use vendor databases separately if you need a company name.

  • Treating normalized text as authorization

    Bit flags summarize the address type from the standard fields; pairing and spoofing concerns still belong to your network policy.

  • Pasting routing next-hops here

    IPv4/v6 gateways belong on the CIDR or IPv6 format pages.

FAQ

Is this the same as a UUID or IP address?

No. MAC / EUI values identify link-layer adapters (typically 48 bits; 64-bit EUI appears in some IEEE contexts). IPs and UUIDs live on different tool pages.

Is data uploaded?

No. Parsing and formatting stay in your tab.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • mac address format colon hyphen online
  • normalize eui-48 hardware address browser
  • cisco mac dotted groups converter
  • multicast mac bit check local admin

More tools

Related utilities you can open in another tab—mostly client-side.