IP Address

An IP address is a unique numeric label that identifies a device on a network. Learn how sending IPs affect email deliverability and reputation.

An IP address is a numeric identifier for a device on a network that helps route email and web traffic.

Definition and examples

An IP (Internet Protocol) address is a unique numerical label assigned to each device connected to a computer network. IP addresses are part of the underlying core of the internet, allowing different devices to find and communicate with each other. IP addresses serve two main functions: identifying the host or network and providing the location of the host in the network.

IP addresses and email sending

In email, the IP address that matters is your sending IP: the address mail providers see your messages come from. Senders on a shared IP pool inherit the pool’s reputation, while a dedicated IP gives you full control of your own. Either way, mailbox providers track the sending IP’s history to decide whether your mail reaches the inbox, which is why new or changed IPs need warming.

Common mistakes

A common mistake is treating this as a one-time technical setup. In practice, it depends on clean sending behavior, monitoring, and steady maintenance.

Related terms

Key takeaways

  • An IP address is a numeric identifier for a device on a network that helps route email and web traffic

  • Your sending IP’s reputation directly affects deliverability

  • Warm up a new or dedicated sending IP before ramping volume

Related: IP warming, Sender reputation, Email deliverability, Email blacklist.