Initialize an external storage device in Disk Utility on Mac — by Apple Support

intermediatepageLink only (©)

Shows how to erase and format an external drive with Disk Utility so the Mac can use it. Includes choosing the partition scheme and file system.

Quick steps

Open Disk Utility and show all devices
Select the drive and click Erase
Choose GUID Partition Map and a format
Name the drive and erase

Paraphrased from the source. Menus can differ by version, so check the original for full details.

Read the full article on support.apple.com

Source: Initialize an external storage device in Disk Utility on Mac by Apple Support. Licence: Link only (©).

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

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