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When I use Disk Utility app in macOS Mojave to format an external drive, I do not see the new Apple File System (APFS) offered as a choice of format.

Does it matter that my external drive is a Toshiba Canvio® Advance Portable External Hard Drive plugged into a MacBook Pro Retina (late 2013) via USB-3 cable? I know APFS is optimized for solid-state storage, so does Disk Utility not offer it for a spinning-metal disk drive?

➥ Why is APFS not offered by Disk Utility?

3 Answers 3

11

If it is not giving you the option for APFS formats, then you are likely trying to format only the logical volume within the container.

To show the container and physical disk in disk utility usually you have to change the view option to "show all devices" from "show only volumes",

Now you can select and format the container as you want.

View APFS

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    You must also select GUID Partition Map. APFS is not available if "Master Boot Record" is selected, which is the default for some pre-formatted disks.
    – WGroleau
    Commented Jul 12, 2023 at 20:50
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Disk Utility will only offer APFS if Partition Map is "GUID Partition Map".

GUID

If the Partition Map is "Master Boot Record" APFS is not an option (and neither is encrypted HFS).

MBR

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  • 3
    I recommend anybody to scroll further down ... this answer only told me what I already knew, but not how to overcome it. The answer apple.stackexchange.com/a/368336/257137 ... gives you that part!
    – GhostCat
    Commented Sep 8, 2020 at 6:04
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    This answer is not really useful, scroll down for the real answer.
    – Ascendant
    Commented Jan 15, 2021 at 18:35
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    This answer will help you if you unmout the existing logical drive, select the whole device and then click on "Delete". Commented Apr 5, 2021 at 18:31
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Edit:

The problem is, that DiskUtil only shows you the Volumes on already partitioned disks. Just select View -> Show all devices. Now instead of the Volume select the device you want to partition and APFS and GUID will be offered.


I was able to get the APFS and GUID scheme option by deleting the MBR

  1. Open a Terminal
  2. Find out which disk is your target: diskutil list
  3. Unmount the disk: diskutil umountDisk /dev/disk# with # being the number of the drive you determined in step 1 (e.g. /dev/disk2)
  4. Delete the MBR: dd if=/dev/zero of=/dev/disk# bs=512 count=1

If you open DiskUtil now you will be offered APFS

Disclaimer

  • Be aware that you are deleting all partitions from the drive
  • Be careful when selecting the disk
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  • This isn't really correct. On GPT formatted disks the first 512 bytes (that you overwrite) contains only the protective MBR which is a pseudo MBR partition table with one partition covering the whole disk. It does not contain the GPT partition table which is in LBA 2 or 3 (see Wikipedia). Perhaps you had a hybrid MBR in which case you have just converted it to an unsafe GPT (i.e. one without protective MBR). Most likely you just had a MBR disk and removed it's partitions.
    – lx07
    Commented Sep 6, 2019 at 16:35
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    Thanks for downvoting, but if OP had GPT there would have been no need to delete it in the first place ;)
    – johnson
    Commented Sep 23, 2019 at 18:45
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    Thanks for this, works as described. On Catalina I had to run the dd command as root, otherwise I got "Permission Denied" error.
    – arcdale
    Commented Jul 25, 2020 at 10:03
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    Thank you very much, this was a life saver!
    – GhostCat
    Commented Sep 8, 2020 at 6:04

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