On TV, lots of terrorist plots have been foiled and bad guys jailed by using their IP address to figure out where they live. Is this possible? Let’s talk about IP addresses.

Your IP address is like a mailing address

You can’t send snail mail without an address, same with IP addresses. Nothing works without it. Every phone and computer has a different IP address, but they can change.

In cities, an address like “5742 37th Ave NW” is like coordinates. I can drive to that address without looking it up on Google. IP addresses aren’t like that, they’re more like rural addresses, you need a special paid service to figure out the physical location.

On WiFi

For WiFi, the entire home or business shares the same IP address. At work, they can usually tell what sites you’re going to, but they have better things to do.

When WiFi is turned on, everyone in your house shares an IP address. An advertiser can't tell the difference between you and your mom. This is how laptops always work.

On 3G, 4G, LTE or 5G

Unlike WiFi, Cellular IP addresses uniquely identify your phone on the internet, but they change a lot. You get a different IP address every time you drive too far and have to attach to a different cell tower. This happens every 0.5-20 miles.

Notice the WiFi logo is gone. Instead it's someting like "3G", "4G" or "LTE".

How do I track down my ex-boyfriend?

If you have an IP address, go to a site like whatismyip.com. It’ll give you a city & state, but it seems wrong because it’s the address of the company that gives you internet service (ISP or phone company).

You can call up the phone company ask them, “where was 71.212.221.55 at 8:17 AM on March 4th?”. They’ll know the answer within a few miles, but this is too much work, so most police & businesses pay for a service that will get a more accurate location.

Can Google or Facebook track me?

Yes, much better than police can.

The hard part is finding an IP address. Only websites can see your IP addresses, not other users on those websites. If Facebook or Google showed your IP address to other users, it would be an absolutely massive security breach. But, police officers can use a warrant to get it from any website (the NSA has better ways).

But Facebook & Google have more options.

• A website can ask you for your location. This is far more accurate than asking the phone company, but they can’t get it if you click “no”.
• Android & iPhone apps. They have to ask for permission, but most people don’t pay attention, so most apps will request far more permissions than they actually need. You might find your grocery store app tracking your location (even though it never works inside the store).

If you have the Facebook Android/iPhone app installed, you don’t have any privacy as long as you’re on your phone. Most other apps aren’t nearly as effective because Facebook has managed to get themselves inserted into nearly every web page you visit (ever see that “Like” button on random websites? It’s tracking you if you’re logged in).

I feel naked. Can I browse the internet alone?

Yes.

• Your browser has a “private” or “incognito” mode. Use it. (Better: Use Tor)
• Uninstall Faceboook from your phone.
• Use Tor instead of your regular browser. This is the absolute best advice. It takes care of everything we’ve talked about but can be a bit clunky to use.