It is important to start with a clarification: "Low-level format" is a commonly misused term.
In the modern era, a true low-level format (defining the tracks and sectors on the physical disk platter) is done at the factory during manufacturing. You generally cannot perform a true low-level format on a modern USB flash drive or SSD at home. Doing so would actually destroy the drive. usb lowlevel format
However, when people ask for a "USB low-level format," they are usually looking for one of two things: It is important to start with a clarification:
Here is a helpful guide on how to achieve these results safely. Zero-filling / Overwriting: Wiping every bit of data
A quick format only deletes the file system's index. With basic recovery software, someone can get your private files back. A zero-fill (low-level format) makes data recovery virtually impossible for non-experts.
Warning: "Low-level formatting" for modern USB flash drives isn't possible the way it was for old hard drives; USB flash memory has embedded controllers and flash translation layers (FTL) that manage physical mapping and wear-leveling. Below is a deep, practical guide covering what low-level formatting means today, how to safely accomplish equivalent tasks, and tools/steps for recovery or secure erasure.