Talk:UDID

12 characters
Isn't the serial 12 characters long? --rdqronos 18:14, 17 March 2012 (MDT)
 * Yes. Actually looking at my old iPod and new one. The old device are 11 characters and the new are 12. I don't know when it started since I only own iPod touch 2G and 4G. --Jacob 18:58, 17 March 2012 (MDT)
 * So then how does one calculate the hash? I tried it with the Serial+ECID+MAC+Bluetooth MAC SHA1 calculation and it was completely different... maybe someone should update this... --rdqronos 20:54, 17 March 2012 (MDT)
 * I can confirm it's not working. I tried with ECID in both upper/lower case, with/without leading zeroes, even in decimal. --http 07:46, 18 March 2012 (MDT)
 * What about with first 11 digits of the serial? --Jacob 14:50, 18 March 2012 (MDT)
 * Not sure what I've done wrong, but now it's working. For people still having problems: There's an app in Cydia called "UDID Calculator", which shows all relevant values. --http 16:32, 23 April 2012 (MDT)
 * I can confirm that it is working at least on my iPad 2 and my iPhone 4 --rud0lf77 12:15, 18 March 2012 (MDT)
 * What format of the ECID did you use? (I don't have Xcode handy.) Hex or dec? Leading zeroes? Upper or lower case? I was trying with my 4S, maybe it has changed again. --http 15:05, 18 March 2012 (MDT)
 * You can get both with redsn0w if people are wondering. Both Hex and Dec. --Dylan Laws 15:39, 18 March 2012 (MDT)
 * Also, what format for MAC addresses should one use? xx:xx:xx:xx:xx or xxxxxxxx --rdqronos 15:46, 18 March 2012 (MDT)
 * To rdqronos: The format for MAC addresses should be clear (see description) if it hasn't changed: including the colons and the letters in lower case. --http 18:56, 18 March 2012 (MDT)
 * Alright. Thanks --rdqronos 19:36, 19 March 2012 (MDT)

iPod touch 1G
To calculate an iPod touch 1G's UDID, shouldn't it be the Bluetooth MAC address that's "00:00:00:00:00:00," not the Wi-Fi MAC address? -- Dialexio 18:51, 23 March 2012 (MDT)

2018 format wrong
I think there's a mistake regarding the 2018 new UDID format. I guess the two parts of UDID must consist of a total 8-char hexadecimal value for the left part of the hyphen, and a 16-char hexadecimal chars, lead by zeros in case the value to display isn't long enough. On the wiki it is stated that the parts are lead by four and three zeros respectively. For example, my iPhone XS UDID begins with  --Habovh 19:14, 6 December 2018 (CET)
 * The page is "wrong" because all of the devices I have checked (my own, and other people's) have had four zeros as part of the second section. I'll investigate this further and see if I can find a pattern with the second section. —  Spydar007  (Talk)  18:53, 6 December 2018 (UTC)
 * That's what I thought, and also the reason why I didn't edit the page directly. I'm sure there's a pattern to be found there! In case it helps, my own iPhone was bought in Europe. --Habovh 11:41, 7 December 2018 (CET)
 * Thanks. Based on a quick look around, it looks like the correct way of describing the second part of the UDID is "the device's ECID, padded with zeros to make it up to 16 characters". I think I may change the first part to match this description as well, just as you said, and make it "an 8-character hex value with zero padding". I'll do some more digging first. —  Spydar007  (Talk)  11:39, 7 December 2018 (UTC)