Visit icloud.com in a web browser and log in with your Apple ID. This will give you access to your iCloud data, including your contacts.


You'll need to be logged in with the same Apple ID on your iPhone for this to work.
 It has the same icon as the Contacts app on your iPhone.
 Press Ctrl/⌘ Cmd+A to select all of the contacts, or hold Ctrl/⌘ Cmd and click each one you want to select.
 You'll find this in the lower-left corner of the screen.
 You'll be asked to confirm that you want to delete the selected contacts. These contacts will be permanently deleted on all of your connected devices, including your iPhone. You cannot retrieve contacts deleted from iCloud.
Log into the iCloud website on any computer.
Open the "Contacts" section of the iCloud site.
Select the contacts you want to delete.
Click on ⚙️.
Select "Delete."
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