Find your iPhone UDID
Open this page in Safari on your iPhone. Scan the code or type the address.
cert.fish/tools/udid
Already on an iPad? Download the profile
With a cable instead
Use this if the profile won't install: a school or work iPhone that blocks profiles, or a one-hour Security Delay from Stolen Device Protection away from home.
Connect the iPhone to a Mac and select it in Finder, or open Apple Devices on Windows. Click the line under the device name until it shows the UDID.
What it is for
A provisioning profile lists the devices it works on by UDID, so a certificate provider needs it to register your iPhone. Certificates and profiles