Bonjour is Apple's tool for finding devices and services on your local network without manual setup

Bonjour is software that lets your computer, printer, phone, and other devices find each other automatically on the same Wi-Fi network. You do not have to type in IP addresses or manually configure anything — Bonjour announces what each device is and what it can do, and other devices listen for those announcements. It is built into macOS, iOS, and iPadOS. On Windows, it installs as a separate program, usually bundled with iTunes or other Apple software.

The name comes from the French greeting, but the technical name is mDNS (multicast DNS) and DNS-SD (DNS Service Discovery). What that means in practice: when you connect a printer to your Wi-Fi, Bonjour tells your Mac or iPhone "there is a printer here, and here is how to talk to it." Your device adds it to the printer list without you having to find its network address or install drivers manually.

Bonjour runs in the background on your computer. Most of the time you do not notice it is there. It only works on your local network — the devices in your home or office — not across the internet.

Key Takeaways

  • Bonjour is Apple software that makes devices on your Wi-Fi network find each other automatically without manual setup.
  • It comes built into macOS and iOS, but on Windows it installs separately, often when you install iTunes or other Apple programs.
  • Bonjour is safe and does not send data outside your home network or to Apple servers.
  • You can disable it if you want, but doing so means manually entering printer addresses and other device details.

Why Bonjour is on your Windows computer

If you have a Windows machine and Bonjour is installed, it came with another Apple program. The most common source is iTunes — Apple bundled Bonjour with iTunes for years so that Windows users could find and stream music to Apple devices on the same network. If you installed iCloud for Windows, AirPrint drivers, or certain other Apple software, Bonjour came along.

You can see whether Bonjour is running by opening Services in Windows. Press the Windows key, type "services.msc" and press Enter. Look for "Bonjour Service" in the list. If it is there and marked "Running," Bonjour is active on your machine.

Apple includes it because many of its programs and devices rely on it to work smoothly with Windows machines on the same network. Removing it will not break your computer, but it may prevent certain features from working — for example, AirPrint printing from a Windows PC to an Apple printer, or streaming to AirPlay speakers.

What Bonjour actually does on your network

Bonjour works by broadcasting information on your local network using a protocol called multicast. When a device joins your Wi-Fi, it announces itself: "I am a printer, my name is HP-LaserJet-4050, and you can reach me at this address." Other devices on the network hear that announcement and add the printer to their available devices list.

The same process works for file sharing, music streaming, video playback, and other services. If you have an Apple TV on your network, Bonjour tells your iPhone and Mac where to find it. If you share a folder from your Mac, Bonjour makes it visible to other Macs without you having to type in a network address.

All of this happens only on your local network — the devices physically connected to your Wi-Fi or Ethernet. Bonjour does not send information to Apple's servers or to the internet. It is confined to your home or office.

Is Bonjour safe?

Bonjour itself is safe. It does not collect personal data, does not phone home to Apple, and does not open ports that expose your computer to the internet. It only works on your local network, so a stranger outside your home cannot use it to find your devices.

The only real concern is that Bonjour makes your devices visible to anything else on your Wi-Fi network. If someone connects to your Wi-Fi without permission, they can see your printer, shared folders, and other services. The solution is the same as for any network security: use a strong Wi-Fi password and keep your network password-protected.

Bonjour does not require a login or password to discover devices — that is by design. If you want to actually use a service (print to a printer, access a shared folder), you may need credentials, but discovery itself is open to anything on the network.

How to disable Bonjour if you do not want it

On a Mac, you cannot easily disable Bonjour because it is built into the operating system. You can turn off individual services that rely on it (like file sharing or AirDrop), but Bonjour itself will keep running.

On Windows, you can disable Bonjour Service. Open Services (Windows key + "services.msc"), find "Bonjour Service," right-click it, and select "Stop." To prevent it from starting again when you restart, right-click it again and set the startup type to "Disabled."

Be aware that disabling Bonjour will break some features. You will not be able to print wirelessly to AirPrint printers without manually entering their IP address. You will not see Apple devices in your network browser. If you use AirPlay or AirDrop, those will stop working. Most people should leave it running.

Bonjour versus other network discovery tools

Bonjour is Apple's version of a broader technology called zero-configuration networking. Other manufacturers use similar systems: Windows has UPnP (Universal Plug and Play), and many printers and routers use SSDP (straightforward Service Discovery Protocol). They all do roughly the same thing — let devices find each other without manual setup.

Bonjour is specific to Apple devices and Apple software, but it also works on Windows machines that have Apple software installed. If you have a Mac, iPhone, iPad, or Apple TV, Bonjour is how they find each other. If you have a Windows PC and want to print to an AirPrint printer or stream to an Apple device, Bonjour is what makes that possible.

The advantage of Bonjour over UPnP is that it is more reliable on home networks and does not require as much configuration. The disadvantage is that it only works with Apple devices and software — a Windows printer will not announce itself via Bonjour.

When Bonjour causes problems

Bonjour rarely causes problems, but when it does, the issue is usually network congestion. On a very large network with hundreds of devices, the constant announcements can use bandwidth. In a corporate office, IT departments sometimes disable Bonjour to reduce network traffic.

Another rare issue is that Bonjour can conflict with other network tools. If you run specialized network monitoring software or have a very restrictive firewall, Bonjour's multicast traffic might be blocked. The symptom is that your devices stop appearing in the available list, even though they are on the network.

If you suspect Bonjour is causing a problem, the first step is to check whether disabling it fixes the issue. If it does, you can decide whether the lost functionality (wireless printing, AirPlay, etc.) is worth the network improvement. Most home users will not notice any difference either way.

Frequently Asked Questions

Does Bonjour send data to Apple?

No. Bonjour only works on your local network. It does not connect to Apple's servers or send any information over the internet. All the announcements and discoveries happen between devices in your home or office.

Can I remove Bonjour from my Windows computer?

Yes. You can disable it through Services, or you can uninstall it through Programs and Features if it was installed as a standalone program. However, removing it will break wireless printing to AirPrint printers and other Apple device features that depend on it.

Why does Bonjour use so much CPU or memory?

Bonjour should use very little CPU or memory — usually less than 1 percent. If it is using a lot, something is wrong. Check whether you have a network problem (too many devices, broadcast storms) or whether another program is using a similar name. Restart your computer and check again.

Will Bonjour work if I am not on Wi-Fi?

Bonjour works on any local network, including Ethernet. If your computer is connected by cable to a router or network switch, Bonjour will still discover devices on that network. It does not require Wi-Fi specifically.

What is the difference between Bonjour and AirPlay?

Bonjour is the discovery tool — it finds AirPlay speakers and Apple TVs on your network. AirPlay is the streaming protocol that actually sends audio or video to those devices. You need Bonjour for AirPlay to work, but Bonjour itself does not stream anything.