Private vs Public IP Addresses Explained
The difference between private IPs used inside your home or office network and the public IP your ISP assigns you.
A private IP address is used inside a local network. Common ranges include 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. These addresses are not routable on the public internet.
How your router bridges the two
Your router performs Network Address Translation (NAT). It assigns private IPs to your devices and, on outbound requests, swaps the source address to its single public IP. Replies come back to the router, which forwards them to the right device.
Why this matters
Many devices in a home share a single public IP. If a website blocks an address, it can affect multiple users on the same network. This is also why your phone and laptop usually appear with the same public IP when on the same Wi-Fi.
常见问题
Can two networks use the same private IP?
Yes — private ranges are intentionally reusable across networks because they never appear on the public internet.
相关内容
- What Is My IP Address? A Plain-English GuideA clear, non-technical explanation of what an IP address is, why websites can see it, and what it does — and does not — reveal about you.
- IPv4 vs IPv6: What Is the Difference?A short, practical comparison of IPv4 and IPv6: address format, why IPv6 exists, and what it means for everyday users and developers.
来源：ip-api 文档、区域互联网注册机构（ARIN、RIPE、APNIC、LACNIC、AFRINIC）以及 BGP 路由数据。