1. Format

2. Usage

3. Calculation

4. References

UDID is an acronym for Unique Device ID. The UDID is a feature of Apple's iOS devices. It is a unique identifier for a single device that is fetched from Apple servers when a user tries to activate the device using iCloud or the Setup app. This ID is also used by iTunes to detect the phone or to communicate with it while restoring the iPSW firmware.

Format

This Unique ID is created from 40 letters and numbers, 25 for an iPhone XR or XS. It is not written on the iDevice cover as the IMEI is, but it can be retrieved by iTunes in normal mode.

Usage

Apple usually uses this ID to assign Apple ID and iCloud ID to the device. This also holds the Find My iPhone activation status.

Calculation

The UDID is calculated as follows:

For the Verizon iPhone 4 and newer:

All other devices use:

References

• [https://www.theiphonewiki.com/wiki/UDID The iPhone Wiki page]
• Cult of MAC Article
• [https://www.getudid.io/ Free Application to find your UDID of iPhone and Ipad etc]

• Will Inman (poet)
• Willin (song)
• Willin Village Archeological Site
• Willi Oberbeck
• Willi Oueifio
• Willi Padge
• Willipete
• Willi Peter Stoll
• Willi-Peter Stoll
• Willi Purstl
• Willi Pürstl
• Willi Railo
• Willi Reinfrank
• Willi Rosenstein
• Willi Rossler
• Willi Rothhaar
• Will Irwin
• Willi Rössler
• Willis Adams
• Willis Adcock
• Willis A. Lee
• Willis A. Lent
• Willi Sanke
• Willi's Antbird
• Willis Antbird