How Can I Get a List of All IP Addresses?

You can obtain a list of IP addresses by checking your own device's configurations, utilizing command-line tools to discover devices on your local network, or by accessing your router's interface. Understanding "all IP addresses" typically refers to your own device's IP addresses (both local and public) and the IP addresses of other devices connected to your local network.

1. Finding Your Own Device's IP Addresses

Every device connected to a network, including your computer or smartphone, has at least one IP address. These can be local (private) or public.

Your Local (Private) IP Address

Your local IP address is unique within your private network (like your home or office network). Your router assigns this IP address to your device.

• On Windows:

  1. Open the Command Prompt by searching for cmd in the Start menu.
  2. Type ipconfig and press Enter.
  3. Look for "IPv4 Address" under your active network adapter (e.g., "Ethernet adapter Ethernet" or "Wireless LAN adapter Wi-Fi"). This is your local IP address. For more details on this command, refer to Microsoft's documentation on ipconfig.

• On macOS:

  1. Go to System Settings (or System Preferences) > Network.
  2. Select your active connection (e.g., Wi-Fi or Ethernet) from the sidebar. Your IP address will be displayed below the connection status.

• On Linux:

  1. Open the Terminal.
  2. Type ip a or ifconfig and press Enter.
  3. Look for the inet address associated with your active network interface (e.g., eth0 for Ethernet or wlan0 for Wi-Fi).

Your Public IP Address

Your public IP address is the IP address that your network uses to communicate with the internet, assigned by your Internet Service Provider (ISP). All devices on your local network share this single public IP address when accessing external websites or services.

• Using a Website: The easiest way to find your public IP address is to visit a dedicated website like whatismyip.com. These sites automatically detect and display your public IP address.

2. Discovering IP Addresses on Your Local Network

To get a list of IP addresses for other devices connected to your local network (like other computers, printers, smart devices, etc.), you can use various methods.

On Windows

You can use built-in command-line tools to discover devices that have communicated with your system:

1. Identify your network gateway: First, open the Command Prompt and type ipconfig. Note down your "Default Gateway" IP address; this is typically your router's IP address (e.g., 192.168.1.1).
2. List connected devices: To get a basic list of IP addresses for devices connected to your network that your computer has recently communicated with, type the command arp -a and press Enter. The arp (Address Resolution Protocol) command displays the ARP cache, which contains a mapping of IP addresses to physical (MAC) addresses for devices on your local network. You will see a list under "Interface" showing "Internet Address" (the IP address) and "Physical Address" (the MAC address) of devices your computer has interacted with. For more information on the arp command, refer to Microsoft's documentation on arp.

On macOS and Linux (Using Nmap)

For a more comprehensive scan of your local network, especially on macOS and Linux, a powerful tool called Nmap (Network Mapper) is highly effective.

1. Install Nmap: If not already installed, you might need to install it. On Debian/Ubuntu Linux, use sudo apt-get install nmap. On macOS, you can install it via Homebrew: brew install nmap.
2. Scan your network: Open the Terminal and use the command nmap -sn <your_network_range>.
   • To find your network range, first identify your local IP address and subnet mask (e.g., 192.168.1.5 with 255.255.255.0). The network range would then be 192.168.1.0/24.
   • Example command: nmap -sn 192.168.1.0/24
   • This command performs a "ping scan" (-sn), which discovers active hosts on the specified network range and lists their IP addresses. You can learn more about Nmap on their official website.

Through Your Router's Web Interface

Your router maintains a list of all devices currently connected to your network. This is often the most straightforward way to see a comprehensive list.

1. Access your router: Open a web browser and type your router's IP address (your "Default Gateway" from ipconfig) into the address bar and press Enter. Common router IPs are 192.168.1.1, 192.168.0.1, or 10.0.0.1. If you don't know it, you can find it using ipconfig (Windows) or ip a (Linux/macOS).
2. Log in: Enter your router's username and password (often found on a sticker on the router itself, or in its manual).
3. Find connected devices: Look for sections like "Connected Devices," "DHCP Clients List," "Network Map," or "Attached Devices." This page will display the IP addresses and often the hostnames or MAC addresses of all currently connected devices. For more assistance, you can find guides on how to log into your router, such as this guide on finding your router IP.

Using Network Scanner Applications

Many third-party applications are designed to scan your local network and provide a user-friendly list of active devices, their IP addresses, and often their device names or manufacturers.

• For Desktop: Applications like Advanced IP Scanner (Windows) or Angry IP Scanner (cross-platform) are popular choices.
• For Mobile: Apps like Fing (iOS and Android) allow you to scan your Wi-Fi network directly from your phone.

Summary Table of IP Address Discovery Methods