Low Level Format on Macbook Pro M1

If that Apple Silicon Mac is running Monterey or later, use the “Erase All Contents and Settings” feature mentioned in the Support article.

I don’t think it does a full reformat of all of the flash sectors of the SSD. It probably marks space as available in whatever way involves a minimum of rewriting / reformatting. (Akin to the standard “fast” erase of a hard disk.)

I believe that it would cause the Apple Silicon chip to change the real-time encryption / decryption keys for the internal SSD, thus effectively turning any existing data into so much useless hash, even if someone found a way to read it.

if the company where you work is named CIA or NSA and the computer contains secrets that would be of interest to the successor to the KGB, you might then want to physically destroy the computer & flash chips afterwards. But if the machine uses real-time encryption in the way I think it does, “Erase All Contents and Settings”will make the data as good as gone, as far as any adversary without unlimited resources is concerned.

To my knowledge, there is no traditional low-level format of an SSD in an Apple Silicon Mac. Further, it's an SSD, so an erase/reformat effectively destroys any data on the disk.

BTW, we are users just like you, we are not Apple Support. If you want to discuss with Apple Support, go here -> Official Apple Support

If what you need to accomplish is to remove all data, for an SSD drive, ERASE will work nicely. Simple data blocks are re-grouped into SuperBlocks are their block numbers randomized, and the SuperBlocks are pre-erased to accept new data. Blocks can not be written unless they have been pre-erased, so the "resting" state of an SSD drive is all unused blocks erased.

Re-writing all data blocks on an SSD drive only shortens its life, it does not improve the thoroughness of data erasure in the slightest.

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For a rotating magnetic drive, only the directory is actually over-written during a quick erase, and since the block numbers are static, 'recovering' some deleted data can sometimes be done with simple aftermarket utilities.

Rotating magnetic drive data blocks are typically overwritten directly by new data, in one pass without an intervening erase, so the 'resting' state of Rotating magnetic drive is unused blocks likely contain stale data and their block numbers are on the Volume's FreeList to be written over when needed to new data.

Hi,

Following article way is good enough for data security, I think.

What to do before you sell, give away, trade in, or recycle your Mac - Apple Support