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Is it possible to format a 512GB mirco SD card as FAT32?

My understanding is that generally speaking you cant format a drive larger than 32GB as FAT32, but I recall there are work arounds for this, but its been a long time since I have done it so I can't recall what they are.

I am trying to format the drive from a Mac running macOS 10.14, but could also use a Windows machine if needed.

Giacomo1968
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sam
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2 Answers2

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Is it possible to format a 512GB mirco SD card as FAT32?

FAT32 can apparently be used with drives up to several terabytes.

My understanding is that generally speaking you can't format a drive larger than 32GB as FAT32[.]

From what I know, this is a Windows-specific limitation (including native tools), assuming it applies.

I am trying to format the drive from a Mac running 10.14, but I could also use a Windows machine if needed.

I am not familiar with Mac, but for Windows you would likely need to use third-party software or PowerShell. This How-To Geek article may be worth a look if you want suggestions on how to accomplish this (on Windows).

Anaksunaman
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Yes. It is possible. The catch is that on some versions of Windows, the resulting card is not always readable. It took me several trials but I got it to work by formatting on Linux where it stays readable.

Most of these commands require you to be running as root, either prepend with sudo or su and then:

  1. gdisk /dev/sdX (Replace X with the letter for your SDXC card - Confirm prompts)
  2. o To overwrite the partition table.
  3. n To create a new partition, confirm all defaults except File-System type. Set it to 0700.
  4. w to write the partition table.

Confirm all prompts. It asks you to reboot to read the new partition table but since an SDXC is removable, you can usually just eject and insert it again. After you can create the filesystem:

mkfs.vfat -s 16 -S 4096 /dev/sdX1

Again, replace X above with the letter for your card. You can pass other values for the sector-size. If this does not work and produces a card you cannot read where you intend to, you can try to format the device instead of having a partition table. In this case, skip the whole gdisk commands and directly create the filesystem in the device itself:

mkfs.vfat -s 16 -S 4096 /dev/sdX

Depending on where it is used, I have seen this work too.

Giacomo1968
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Itai
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