Why Your Printer Has More Than One Kind of IP Address
Public and private IP addresses serve different purposes in a printer network. A private IP address identifies a printer inside a home, office, school, or other local network, allowing computers and mobile devices on that network to find it. A public IP address identifies the internet connection at the network edge and is normally assigned to a router or firewall, not directly to a printer. Understanding the distinction helps users configure reliable printer connections, reserve addresses, diagnose discovery failures, and avoid unsafe attempts to expose printing devices to the internet. This guide explains address ranges, NAT, remote printing options, practical setup steps, and essential security measures for printers and scanners.
Network printers and multifunction devices depend on IP addresses to communicate with computers, phones, print servers, and scanning destinations. Yet an IP address shown on a printer’s control panel is usually not the same type of address that represents your internet connection. The practical distinction between public and private IP addresses explains why a printer works from one room but not from outside the office, why its address can change unexpectedly, and why directly opening it to the internet is usually a serious security mistake.
The basic distinction
An IPv4 address is a numeric label such as 192.168.1.45. It helps devices send traffic to the right destination. Private addresses are used inside local networks, while public addresses are globally routable across the internet.
A network printer almost always receives a private address from the router, firewall, or DHCP server. A laptop on the same Wi-Fi or Ethernet network can use that address to print through IPP, AirPrint, Windows printing, RAW port 9100, or another supported protocol. The router then separates this internal network from the public internet connection.
Private IP addresses in printer networks
Private IPv4 ranges are reserved for internal use. They can be repeated in millions of unrelated homes and businesses because they are not routed on the public internet. For example, a printer at 192.168.1.45 in one office has no relationship to a printer with the identical address elsewhere.
| Address type | Common IPv4 ranges | Typical printer role | Internet reachability |
|---|---|---|---|
| Private | 10.0.0.0–10.255.255.255 | Large organizations and managed sites | Not directly routable |
| Private | 172.16.0.0–172.31.255.255 | Business VLANs and segmented networks | Not directly routable |
| Private | 192.168.0.0–192.168.255.255 | Homes, small offices, and many printer setups | Not directly routable |
| Public | All globally assigned, non-reserved ranges | Router or firewall WAN interface | Potentially routable, subject to firewall rules |
On a printer, the private address may appear on a network configuration page, under menus such as Network, Ethernet, Wi-Fi, or TCP/IP. It is the address to use when manually adding the device from a computer on the same local network.
Why a printer address may change
Most routers use DHCP to lend addresses for a limited period. After a restart, lease renewal, or network change, a printer might receive a different private IP address. A print queue configured with the old address can then show the printer as offline even though the device is working.
- Use a DHCP reservation in the router or DHCP server for the printer’s MAC address.
- Alternatively, assign a static address outside the automatic DHCP pool, following the network administrator’s plan.
- Record the printer’s hostname as well as its address when the device supports reliable DNS or mDNS discovery.
- Keep the printer and client devices on network segments that are permitted to communicate.
What a public IP address does
A public IP address is generally assigned by an internet service provider to the router, gateway, or firewall facing the internet. Websites and external services see this public address when devices behind the router make outbound connections. It is not normally assigned to individual printers.
The reason is network address translation, commonly called NAT. NAT lets many devices using private addresses share one public address. When a computer sends a print job to a local printer, the traffic stays inside the local network and does not need a public IP address. When the printer checks for firmware updates or connects to an approved cloud service, the router translates its private source address for the outbound internet connection.
A public IP address is an address for the network boundary, not an invitation to publish every device behind that boundary. Printers should remain protected behind a firewall unless a managed, explicitly secured design requires otherwise.
How this affects printing and scanning
For ordinary local printing, private addressing is all that matters. A Windows PC may add a printer by its hostname or IP address, while a Mac, iPhone, or iPad may discover it through AirPrint. In a managed workplace, a print server can publish queues to users and communicate with printers on dedicated VLANs.
Scanning introduces similar considerations. Scan-to-network-folder, scan-to-email, and scan-to-cloud features need correctly configured local routing, DNS, credentials, and firewall rules. A scanner sending a file to a local server uses private addresses. A scanner reaching an external email provider or cloud platform makes an outbound connection through the router’s public address and firewall.
Local access versus remote access
If you are away from the building, typing the printer’s private address into a browser will not work because that address only exists on the local network. Typing the public address is not a safe substitute. Even if port forwarding has been configured, exposing a printer’s web interface or print protocol can create opportunities for unauthorized printing, data exposure, or device compromise.
Safer remote alternatives include:
- A company VPN that authenticates users before granting access to internal print resources.
- A managed print server or secure cloud-printing platform approved by the organization.
- Vendor-supported remote services that use authenticated outbound connections and are kept updated.
- Sending documents to a trusted colleague or centralized print workflow rather than opening printer ports.
A practical setup checklist
When installing a printer on a home or small-office network, focus on a stable private address and the correct local connection method. Do not change the router’s public-address settings unless the internet provider or network administrator directs you to do so.
- Connect the printer to the intended Ethernet or Wi-Fi network and print its network configuration report.
- Confirm that its IPv4 address is private, such as
192.168.x.x,10.x.x.x, or an address within the private 172.16–172.31 range. - From a computer on the same network, open the printer’s local web interface using
https://followed by the printer address, if HTTPS is supported. - Create a DHCP reservation in the router or ask the network administrator to reserve the address.
- Add the printer using the manufacturer’s recommended driver, IPP, AirPrint, or the organization’s print server.
- Print a test page and test scanning separately, because successful printing does not guarantee that scan destinations are configured correctly.
- Change default administrator credentials, update firmware, and disable unused services.
Troubleshooting common address problems
If a printer appears offline, first compare the address stored in the computer’s printer settings with the address on the printer’s current network report. If they differ, update the queue or restore the reserved address. If they match, test whether the computer can reach the printer’s web interface and verify that both devices are on compatible networks.
Guest Wi-Fi, client isolation, and separate VLANs often prevent discovery or direct printing. A phone on guest Wi-Fi may have internet access but be intentionally blocked from reaching a printer on the staff network. In that case, moving the client to the approved network or asking an administrator to configure controlled access is preferable to weakening network isolation.
Signs that need administrative attention
- The printer has an address outside the expected subnet, such as a 169.254.x.x self-assigned address.
- The printer repeatedly changes address despite a configured reservation.
- Its administration page is reachable from outside the organization without a VPN.
- Unknown print jobs, changed settings, or unfamiliar administrator accounts appear.
- Firmware is obsolete or the device no longer receives security updates.
Security practices for connected printers
Printers store documents in memory, process credentials for scan workflows, and may provide a web administration interface. Treat them as networked computers rather than simple peripherals. Keep them on a trusted network, apply current firmware, use unique administrative passwords, and restrict management access to authorized users. In larger environments, separate printer traffic into a dedicated VLAN and permit only the required paths to print servers, DNS, email relays, and scan destinations.
Disable legacy services that are not needed, especially insecure management protocols. Prefer encrypted administration over HTTPS and secure print protocols where supported. Most importantly, do not use port forwarding to make a printer directly reachable from the public internet merely to enable remote printing.
