Your Mac, and any external drives you use, may contain important personal data. If you are having trouble fixing this problem with the instructions above, but are being able to solve this problem with any another method please describe it in the comment section below.How To How to Securely Erase Data from Your Mac and External Drives We can leave our flash drive in the FAT32 format or convert it to any other format using the Disk Utility app. We reclaimed full capacity on flash drive, and make it available for saving data again now. Once the process begins, all the data on the flash drive will be lost!Ģ: Apple_APFS Container disk1 250.7 GB disk0s2Ġ: APFS Container Scheme - +250.7 GB disk1ġ: APFS Volume Macintosh HD 125.3 GB disk1s1 This process is data destructive and cannot be undone.

This tool is built-in in macOS, so we do not need to download or install anything.Ĭritical! The instructions in the article below are designed to help format a flash drive. To solve this issue, we will use the Terminal app and the tool diskutil. The Disk Utility app does not see this hidden partition and therefore formats only the first partition instead of the two. To use a flash drive as a boot disk (for example, with the OS for Raspberry Pi), it creates two partitions: the first one with the bootloader and occupies 60 MB, the second one with the OS files is a hidden partition and occupies the rest of the flash drive space. In my case it’s all about the type of previous formatting. This is not a problem with the flash drive at all. And it can happen with a flash drive from any manufacturer. If I try to format it using macOS built-in Disk Utility app, it will only free the space in that partition. I noticed that no matter the size of my SD memory card, after writing an image with OS for my Raspberry Pi, macOS can only recognize one partition with about 60 MB. In this article I will show you how to format a flash drive to reclaim full capacity and make it available for saving data again now. Have you ever met this problem that a flash memory card or USB flash drive is not showing the full capacity but a wrong size in macOS? I got this problem every time when trying to erase an SD memory card after working with Raspberry Pi.

Erase usb drive mac