What Is a Private IP Address?
2026-01-21
What Is a Private IP Address?
A private IP address is an IP address used inside a local network (LAN), such as your home Wi‑Fi, office network, or internal corporate systems. Private IP addresses are not directly accessible from the public internet.
They allow devices within the same network to identify and communicate with each other efficiently and securely.
How Private IP Addresses Work
When multiple devices connect to a router:
- The router assigns each device a private IP address.
- Devices use these private IPs to communicate locally.
- When accessing the internet, the router translates private IPs into a public IP using NAT (Network Address Translation).
This design allows many devices to share a single public IP address.
Common Private IP Address Ranges
Private IP addresses are defined by international networking standards (RFC 1918).
IPv4 Private IP Ranges
10.0.0.0 – 10.255.255.255172.16.0.0 – 172.31.255.255192.168.0.0 – 192.168.255.255
These ranges are reserved exclusively for internal use.
Private IP vs Public IP
| Feature | Private IP | Public IP |
|---|---|---|
| Visibility | Local network only | Internet‑wide |
| Assigned by | Router / DHCP | ISP |
| Purpose | Internal communication | Global communication |
| Internet access | Via NAT | Direct |
Private IP addresses protect internal devices from direct exposure to the internet.
Why Private IP Addresses Are Important
Private IPs are essential because they:
- 🛡️ Improve network security
- 🌐 Reduce public IP usage
- 🖥️ Enable large internal networks
- ⚙️ Simplify device management
Without private IP addressing, the internet would have run out of IPv4 addresses much earlier.
Private IP Addresses and NAT
NAT (Network Address Translation) allows routers to map multiple private IP addresses to a single public IP address.
Benefits of NAT include:
- Address conservation
- Basic traffic filtering
- Internal network isolation
NAT plays a crucial role in modern IPv4 networks.
Do Private IP Addresses Change?
Yes, in most cases.
- Assigned dynamically via DHCP
- May change when devices reconnect
- Can be set manually (static private IP)
Static private IPs are often used for printers, servers, or network devices.
Can Two Networks Have the Same Private IPs?
Yes.
Private IP addresses are not globally unique. Multiple separate networks can use the same private IP ranges without conflict because they are isolated from each other.
How to Find Your Private IP Address
You can check your private IP directly on your device.
On macOS / Linux:
ifconfig
On Windows:
ipconfig
Look for addresses starting with 192.168, 10., or 172.16–31.
Private IP and IPv6
IPv6 also supports private-style addressing, such as:
- Unique Local Addresses (ULA)
However, IPv6 is designed to reduce the need for NAT and private addressing by providing abundant global addresses.
Summary
A private IP address is a key part of local networking:
- Used within internal networks
- Not accessible from the internet
- Works alongside public IPs via NAT
- Improves security and scalability
Understanding private IP addresses helps you better manage networks, troubleshoot connectivity issues, and grasp how the internet operates behind the scenes.
IP Web Tools can help you analyze both your private and public IP information with ease.