Ever since the iPhone was released in 2007, Apple has had a four digit passcode as a default. But with forthcoming iOS releases, Apple introduced characters and letters if users wanted to take advantage of a little extra security.
With iOS 9, Apple has added a six digit passcode as an option for those who want a little better peace of mind but don’t want the hassle of using letters and characters in their passcode.
1. Go to Settings.
2. Tap on Passcode.
3. Enter your current passcode if you have one.
4. Tap on Change Passcode.
5. Tap on Passcode Options.
6. Select 6-Digit Numeric Code.
7. Type in your new passcode.
8. You’ll then be asked if you want to use the new passcode as your iCloud security code.
If you want to change revert back to a four digit passcode, just repeat the steps above but select the 4-Digit Numeric Code option.