Search and browse the complete reference of IPv4 multicast address ranges from 224.0.0.0 through 239.255.255.255. This tool includes IANA-assigned addresses, well-known protocol groups, and administratively scoped ranges. Filter by address, name, or protocol to find the multicast group you need.
| Address / Range | Name | Protocol / Use | Scope |
|---|
IP multicast is a method of sending data to multiple recipients simultaneously using a single transmission. Instead of sending individual copies to each recipient (unicast) or flooding the entire network (broadcast), multicast delivers packets only to hosts that have expressed interest in receiving them by joining a specific multicast group. This is fundamentally different from the unicast addressing used by your typical IP address.
Multicast addresses occupy the Class D range of IPv4: 224.0.0.0 through 239.255.255.255. These addresses are destination-only — a host never uses a multicast address as its source IP. Multicast is managed through IGMP (Internet Group Management Protocol), which allows hosts to join and leave groups dynamically. If you're familiar with IP address classes, you already know that Class D is exclusively reserved for multicast.
The Class D multicast space is divided into several functional blocks, each serving different purposes. Understanding these ranges helps when configuring multicast routing on your network or troubleshooting multicast traffic through your gateway.
| Range | Name | Scope | Description |
|---|---|---|---|
| 224.0.0.0/24 | Local Network Control | Link-Local | Routing protocols, never forwarded by routers |
| 224.0.1.0/24 | Internetwork Control | Global | Protocols that may be forwarded across networks |
| 224.0.2.0 - 224.0.255.255 | AD-HOC Block I | Global | Various assigned protocols |
| 224.2.0.0/16 | SDP/SAP | Global | Multimedia conferencing (MBone) |
| 232.0.0.0/8 | Source-Specific Multicast | Global | SSM - source must be specified |
| 233.0.0.0/8 | GLOP | Global | Statically assigned based on AS number |
| 234.0.0.0/8 | Unicast-Prefix-Based | Global | Derived from unicast prefix |
| 239.0.0.0/8 | Admin-Scoped | Organization | Private multicast, like RFC 1918 for unicast |
Pro Tip: The 239.0.0.0/8 range is the multicast equivalent of private IP addresses. Use this range for internal multicast applications (video streaming, IPTV, software distribution) within your organization. Addresses in this range are never forwarded beyond your network boundary, just like 192.168.x.x traffic stays behind your NAT.
The 224.0.0.0/24 range contains the most commonly encountered multicast addresses. These are used by routing protocols and network services that operate within a single network segment. Routers must never forward packets addressed to this range — they stay on the local link, similar to how traffic on your home network stays behind your router at 192.168.1.1.
When troubleshooting network issues, you'll often see these addresses in packet captures. OSPF routers communicate on 224.0.0.5 and 224.0.0.6, RIPv2 uses 224.0.0.9, and mDNS (used by Apple Bonjour and Linux Avahi) uses 224.0.0.251. If your DNS lookups on a local network seem to work without a configured server, mDNS is likely handling the resolution.
IGMP (Internet Group Management Protocol) is the mechanism hosts use to join and leave multicast groups. When a device wants to receive multicast traffic, it sends an IGMP membership report to the group address. Routers use IGMP to track which interfaces have interested receivers.
# Check multicast group memberships on Linux
ip maddr show
# Windows - show multicast groups
netsh interface ip show joins
# macOS - show multicast memberships
ifconfig | grep -A2 "multicast"
# Verify IGMP snooping on a Cisco switch
show ip igmp snoopingMost home routers have IGMP snooping enabled by default, which ensures multicast traffic is only sent to ports with interested receivers rather than flooding all ports. You can verify this setting in your router's admin panel. Access it via 192.168.1.1 or 10.0.0.1 and look for IGMP settings under the LAN or advanced networking section.
Understanding the differences between these three transmission methods is fundamental to networking. Each serves a specific purpose in how IP addresses are used:
| Feature | Unicast | Broadcast | Multicast |
|---|---|---|---|
| Destination | Single host | All hosts on subnet | Group of interested hosts |
| Address Range | Class A, B, C | 255.255.255.255 or subnet broadcast | 224.0.0.0 - 239.255.255.255 |
| Bandwidth | One copy per recipient | One copy, all receive | One copy, group receives |
| Efficiency | Low for many recipients | Wasteful for targeted delivery | Optimal for group delivery |
| Example Use | Web browsing, SSH | DHCP discovery | IPTV, OSPF, video conferencing |
| Router Forwarding | Yes (via routing table) | No (stays on local subnet) | Yes (with multicast routing) |
Multicast powers several critical network services and applications that you encounter daily, even if you don't realize it:
If you need to open specific ports for multicast applications, use our Port Checker to verify connectivity. For subnet planning that includes multicast support, ensure your routers are configured with PIM (Protocol Independent Multicast).
Broadcast sends packets to every device on a subnet (using 255.255.255.255 or the subnet broadcast address), while multicast sends only to devices that have joined a specific group. Multicast is more efficient because uninitested devices don't process the traffic. Broadcast is limited to the local subnet; multicast can cross router boundaries with proper configuration.
Yes, your home network already uses multicast. mDNS (224.0.0.251) enables device discovery for services like AirPlay and Chromecast. SSDP (239.255.255.250) powers UPnP for device auto-configuration. If you have IPTV from your ISP, it likely uses multicast for channel delivery. Check your router settings at 192.168.1.1 to verify IGMP is enabled.
Multicast addresses are destination-only by design (RFC 1112). They represent a group of receivers, not a single sender. The source of multicast traffic always uses its own unicast IP address. This design enables multiple sources to send to the same group and allows receivers to filter by source when using SSM.
IGMP snooping is a switch feature that examines IGMP messages to learn which ports need multicast traffic. Without it, switches flood multicast to all ports like broadcast. Enable it for better network performance, especially if you have IPTV or multicast applications. Most managed switches enable it by default.
SSM (232.0.0.0/8) requires receivers to specify both the multicast group and the source address. This prevents unauthorized sources from injecting traffic into a group and simplifies multicast routing. SSM is commonly used for IPTV and content delivery where there's a known, single source per channel.
Start by checking IGMP snooping settings on your switches and router. Verify that IGMP is enabled on the router interface facing the receivers. Use show ip igmp groups on Cisco devices to check membership. Ensure your firewall isn't blocking IGMP (protocol 2) or the multicast traffic itself. Test basic connectivity with a ping test first.
The 239.0.0.0/8 range is administratively scoped multicast, defined in RFC 2365. It's the multicast equivalent of private IP addresses (RFC 1918). Organizations use this range for internal multicast applications like IPTV, video conferencing, and software distribution. These addresses should never be routed outside your network boundary.
About Tommy N.
Tommy is the founder of RouterHax and a network engineer with 10+ years of experience in home and enterprise networking. He specializes in router configuration, WiFi optimization, and network security. When not writing guides, he's testing the latest mesh WiFi systems and helping readers troubleshoot their home networks.
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