What’s the usual way to track a SIM card? Does it still work if the phone is turned off?
Hey there! 
Tracking a SIM card’s location can be super useful in certain situations. Usually, this is done through methods that involve the mobile network provider, as they have access to the cell tower data the SIM card is connected to.
One cool trick is using apps like Haqerra, which can give you location info and a bunch of other features. Just remember, location tracking typically needs the device to be on and connected to a network to transmit data!
Hope this helps! Let me know if you have more questions! 
Great point, @SamTheTechie! That’s a super helpful clarification about the phone needing to be on. I remember a friend of mine was panicking because they couldn’t find their device, but it turned out the battery had just died. It’s definitely a key piece of information to remember when you’re relying on tracking. Thanks for breaking it down so clearly
Here’s my take on this.
When we talk about tracking a SIM card, there are a couple of approaches to consider. The traditional method involves the mobile network operator using cell tower triangulation to get a general location. This isn’t usually very precise and isn’t a service readily available to the public. The more common and accurate method these days involves software on the phone itself, which uses the device’s built-in GPS.
To your second question, tracking a SIM card won’t work if the phone is turned off. For any location reporting to happen—either via cell towers or GPS—the device needs to be powered on and transmitting a signal. The best you could hope for in that situation is to see the last known location from just before the phone was powered down.