A MAC address identifies a piece of network hardware. An IP address identifies where a device sits on a network right now.
If you remember one thing from this page, make it this: your MAC address never leaves your local network. The websites you visit cannot see it, your ISP does not receive it, and no analytics tool records it.
That single fact settles most of the questions people actually have about these two, including several that circulate as confident misinformation.
You will also find one very common claim about MAC addresses repeated across the top results for this question, and it stopped being true around 2020. That is covered below.
Quick Comparison
| MAC address | IP address | |
|---|---|---|
| Identifies | A network interface | A location on a network |
| Assigned by | The hardware manufacturer | The network, via DHCP or manually |
| Format | A4:83:E7:1B:9C:2D | 192.168.1.14 or 2001:db8::1 |
| Network layer | Layer 2, data link | Layer 3, network |
| Travels | One hop only | End to end across the internet |
| Changes | When you switch networks, on modern phones | Whenever the network reassigns it |
| Visible to websites | Never | Always |
The Part That Explains Everything Else
The usual analogy is that the IP is your address and the MAC is your name. It is not quite right, and the better version explains far more.
Think of sending a parcel. The IP address is written on the parcel and stays there for the whole journey, from your house to the destination.
The MAC address is how each depot hands the parcel to the next van. It matters only for that one leg. At the next depot it is replaced with a new one.
What Routers Actually Do
When your laptop sends data to a website, it wraps the data with the destination IP address, which does not change, and the MAC address of your router, which does.
Your router receives it, strips off the MAC information entirely and rewrites it for the next hop. This happens at every router along the way, perhaps a dozen times.
By the time your request reaches the web server, the original MAC address is long gone. The server sees only an IP address, and even that is usually your router’s public one rather than your device’s.
Why This Matters
People worry about websites tracking them by MAC address, and ask how to hide it from advertisers. The answer is that there is nothing to hide, because nothing left the building.
Equally, if you are trying to identify a specific device from your web analytics, you cannot. The MAC address is not in the data and never was.
What a MAC Address Is
A MAC address is a 48-bit identifier assigned to a network interface, written as six pairs of hexadecimal digits.
Every network interface has one. A laptop with Wi-Fi and Ethernet has two different MAC addresses, one per interface, and adding a USB network adapter adds a third.
The First Half Tells You the Manufacturer
The first three pairs are the OUI, the Organisationally Unique Identifier, registered to whichever company made the interface. The rest identifies the individual device.
This is genuinely useful when you are looking at a list of connected devices on your router and trying to work out what an unlabelled entry is. Paste the first six characters into any OUI lookup tool and you will usually get a manufacturer name, which narrows it down quickly.
What an IP Address Is
An IP address is assigned by the network, not by the hardware, which is why it changes when you move between networks.
The important split is private versus public. Your device holds a private address on your local network, something like 192.168.1.14, which is meaningless outside your building. Your router holds one public address, which is what the rest of the internet sees.
Everything in your home or office shares that single public address, a mechanism called NAT. So a website cannot tell your laptop from your phone by IP either.
Most addresses are assigned automatically by DHCP, which hands out an address with a lease that eventually expires. Static addresses are set manually and stay put, which is why servers use them.
How the Two Work Together
On your local network, devices need to convert an IP address into the MAC address it belongs to, so they know which physical interface to send a frame to.
That job belongs to ARP, the Address Resolution Protocol. It effectively shouts across the local network asking who holds a given IP, and the device with that address answers with its MAC.
So the two are not competitors. IP gets data to the right network, MAC gets it to the right device once it arrives.
The Claim That Is No Longer True
Read the top results for this question and you will be told that a MAC address is permanent, burned into the hardware and never changes. It is the standard textbook line.
For phones and laptops on Wi-Fi, that has been wrong since around 2020.
MAC Randomisation
Modern operating systems generate a fake MAC address for each Wi-Fi network you join, specifically so networks and advertisers cannot follow a device between locations.
- iOS 14 and later, called Private Wi-Fi Address, on by default. It creates one random address per network and reuses it for that network.
- Android 10 and later, on by default. From Android 12 the addresses became non-persistent, changing as often as every 24 hours.
- Windows 11, supported but opt-in rather than on by default.
The hardware address still exists underneath. It simply is not what the network sees any more.
What This Broke
Two things that used to work stopped working, and both catch people out.
MAC-based Wi-Fi allow-lists now need re-approving whenever a device’s randomised address rotates, which is why offices and universities publish instructions for turning the feature off.
Wi-Fi footfall analytics also largely collapsed. Counting unique visitors in a shop by logging the MAC addresses of passing phones no longer produces meaningful numbers, because one phone can present many addresses.
Where Each One Actually Shows Up in Web Work
If you work on websites or marketing rather than networks, this is the section that matters, and no guide on this question covers it.
The short version: IP addresses appear constantly, MAC addresses appear never.
Things IP Addresses Decide
- Approximate location. Country level is usually reliable, city level much less so. This is what geo-redirects and country-level ad targeting run on.
- Search results. Your IP is a strong signal for which country’s results Google returns.
- Analytics filtering. Excluding your own team’s visits from reports is normally done by IP.
- Rate limiting and blocking. Firewalls, login throttling and bot protection all work per IP.
- Server logs. Every request your server records is stamped with one.
The Practical Trap: Internal Traffic Filters Break
Setting up an IP filter to exclude your own visits is standard practice. It quietly stops working, and here is why.
Most business and home connections have a dynamic public IP. Your provider can change it after a router reboot, a line fault or maintenance.
When it changes, your filter is now excluding somebody else’s address and letting all of your own traffic back into the reports. Nothing errors, the numbers just get slightly wrong.
Three ways to deal with it: ask your provider what a static IP costs, re-check the filter periodically, or filter on something more stable than an IP where the tool allows it.
The same applies to any allow-list you maintain by IP, including admin access rules.
Things MAC Addresses Decide
In web and marketing work, nothing at all. They matter when you are managing the network itself: identifying devices on a router, setting a fixed DHCP reservation for a printer, or tracking down which machine on the office network is misbehaving.
MAC Filtering Is Not Security
Restricting a Wi-Fi network to an approved list of MAC addresses feels like a lock. It is closer to a sign.
MAC addresses are sent in the clear on wireless networks, including by devices already connected. Anyone within range can read the approved ones with freely available software.
Changing your own device’s MAC to match takes a single command on most operating systems. There is no cryptography to defeat.
Use MAC filtering if you want, as a way of keeping honest devices tidy. It is not a substitute for a strong WPA2 or WPA3 passphrase, and treating it as one is a familiar pattern in small business security: a control that looks protective while the real protection sits elsewhere.
What Each One Reveals About You
An IP address reveals roughly where you are and who provides your connection. It does not reveal your name or address to a website, though your provider can link it to your account and may be required to.
A MAC address reveals the manufacturer of your hardware, and identifies that interface uniquely, but only to devices on the same local network. A coffee shop’s Wi-Fi sees it. A website does not.
So the privacy tools people reach for match the problem in one case and not the other. A VPN or proxy changes the IP a website sees, which is the address that actually leaves your network. Nothing needs to hide your MAC from websites, because it was never going there.
Frequently Asked Questions
Can a website see my MAC address?
No. MAC addresses only travel one hop, and every router along the path strips and replaces them. By the time your request reaches a web server, the original MAC is gone. The server sees an IP address, and usually your router’s public one rather than your device’s.
What is the main difference between an IP address and a MAC address?
A MAC address identifies a specific piece of network hardware and only has meaning on the local network. An IP address identifies where a device sits on a network and travels end to end across the internet. IP gets data to the right network, and MAC gets it to the right device once it arrives.
Does a MAC address ever change?
Yes, despite the common claim that it never does. Since iOS 14 and Android 10 phones generate a randomised MAC address for each Wi-Fi network by default, and Android 12 and later rotate it as often as every 24 hours. Windows 11 supports the same feature as an opt-in setting. The underlying hardware address still exists, but it is not what the network sees.
Is MAC address filtering good security?
No. MAC addresses are broadcast in the clear on wireless networks, so anyone in range can read the approved list, and changing a device’s MAC to match takes one command. Use it for tidiness if you like, but rely on a strong WPA2 or WPA3 passphrase for actual protection.
Why does my Google Analytics internal traffic filter stop working?
Almost always because your public IP address changed. Most business and home connections have dynamic IPs that the provider can reassign after a reboot, fault or maintenance, at which point the filter excludes a stranger’s address and your own visits reappear in the reports. Nothing errors, so check it periodically or ask your provider about a static IP.
How do I find out what a device on my network is?
Take the first six characters of its MAC address, the part known as the OUI, and paste them into any OUI lookup tool. That returns the manufacturer of the network interface, which usually narrows an unlabelled entry on your router down to something recognisable.
Does a VPN hide my MAC address?
It does not need to. A VPN changes the IP address websites see, which is the identifier that actually leaves your network. Your MAC address was never reaching those websites in the first place, so there is nothing for a VPN to conceal there.
Can two devices have the same IP address?
On the same network that causes a conflict and breaks connectivity for both. Across different networks it is normal, because private ranges like 192.168.1.x are reused in millions of homes and offices. Everything behind one router also shares a single public IP address, which is why a website cannot distinguish your laptop from your phone by IP alone.