Largest FAT File System on SDCard?

[persistentone]

What is the largest size FAT file system to which both Android and Windows 8 will support both reading and writing? I thought the limit was 32GB. Somehow I ended up with a 64GB SDCard with exFAT on it and that is working between the two operating systems.

Assuming a 128 GB SDCard will work, should I be doing the initial format of that under Android, or under Windows? Do I need any special format settings under Windows, or does it require a third party utility?

 

[mikedt]

FAT32 can actually support up to 2TB drives capacity, however file size limit is only 4GB. I've got a 2TB USB HDD that I formatted as FAT32, mainly because I wanted to use it with some devices, like a TV that only supported FAT32 drives.

I don't use Windows myself, but it could be the default with Windows 8 & 10 for removable storage is exFAT? AFAIK Android 8 and above does support exFAT. I've got a 512GB micro-SD in my phone that's formatted as exFAT.

 

[svim]

What is the largest size FAT file system to which both Android and Windows 8 will support both reading and writing? I thought the limit was 32GB. Somehow I ended up with a 64GB SDCard with exFAT on it and that is working between the two operating systems.

Assuming a 128 GB SDCard will work, should I be doing the initial format of that under Android, or under Windows? Do I need any special format settings under Windows, or does it require a third party utility?

FAT and each of its variants are owned by Microsoft so Windows support for it is a given.
But it's very dated and even Microsoft stopped putting development support for it years ago when it moved to NTFS -- FAT file systems weren't all that stable and robust even in their day, now it's a mess that we're all just stuck with. Currently Microsoft continues to allow other platforms to include basic support for it but FAT is still proprietary so other companies are legally prevented from any more. USB storage media continues to rely upon FAT32 or exFAT as a default, despite all its faults -- i.e. weak support for file/folder permission in other platforms; restrictions on file metadata; and as you've brought up, file and storage media limitations.
https://en.wikipedia.org/wiki/File_Allocation_Table