How do I check my iPhone's IMEI on Apple's website?

Apple does not track IMEI.

There are online sites that claim to be able to check the IMEI, but I have not found one that I would recommend. Most offer a "free" IMEI check, but you usually have to pay to get any thing that might be useful.

If you do have the IMEI number and you want to make sure that the phone has not been blacklisted, contact the carrier that you plan on using and ask them to run a check.

We hear multiple nightmare stories each day from users who have bought a used phone, which turns out to be useless.

NEVER buy a used phone online. You need to have the phone in your hands to make sure that it starts up to the "hello" screen. Make sure that you have a written money back guarantee that will allow you to return the phone within 7-14 days if you are not satisfied.