WARNING: Formatting will erase all data on the device. Back up all your data before proceeding.

Instructions below are for 10.11.x (El Capitan) and 10.12.x (Sierra)

1. Double-click on Macintosh HD - or in the Finder menu clickFile > New Finder Window
2. Click the Applications folder - if using a Finder Window Applicationswill be in the left side menu.
3. Click the Utilities folder.
4. Double-click Disk Utility.
5. On the left side of the window are the drives connected to the computer. Select the capacity of the drive respective to the one containing the device you wish to format then click the Erase tab.
Example: If the drive is called 'NO NAME', directly above that, you should see the drive capacity of 'XXXX'. Select this capacity.
6. Verify Volume Format is set to MS-DOS file system or exFAT, Scheme is set to “Master Boot Record” (Do NOT select GUID Partition Map) then click Erase.

How to Format a USB Flash Drive on Mac? Kamran Sharief, 5 months ago 0 USB or Universal Serial Bus flash drives are one of the most popularly used portable storage devices due to its compact size and high storage capacity which makes it suitable for data transfer between various devices. The overwhelming majority of USB flash drives you buy are going to come in one of two formats: FAT32 or NTFS. The first format, FAT32, is fully compatible with Mac OS X, though with some drawbacks. How to Format USB Flash Drive on Mac OS? Open Disk Utility on Mac. Select the target USB flash drive in the left sidebar, then click Erase at the top bar. Select MS-DOS (FAT) in the Format selectbox. Check all options one more time, then click Erase to. Once the flash drive shows up on the desktop, right-click on the drive icon and click Get Info. Now, in the dialog box, you’ll notice your USB Drive’s file system next to the Format option. In my case, it’s.

Instructions below are for 10.13.x (High Sierra)

1. Open Disk Utility. Please See Answer 20985: How to access Disk Utility macOS
2. In the top menu bar, go to View, and choose Show All Devices

3. Select the upper level of the drive you would like to format and click the Erase button

4. Choose how you would like to format the drive

Format Pen Drive On Mac

Enter a Name for your drive
Choose exFAT or MS-DOS (FAT) for the format
Choose Master Boot Record for the Scheme
Click Erase

5. When finished, the drive will be formatted and repartitioned successfully. Click the Done button

NOTE: exFAT is used on SDXC card (64GB and higher).

NOTE: exFAT can be used on flash drives or memory cards to transfer files larger than 4GB.

NOTE: MacOS 10.6.2 or higher is required for exFAT file system. Some older operating systems must have a patch installed before they can use the exFAT file system.

NOTE: If the above steps do NOT resolve the problem or if the lock switch is missing or broken, please back up your data and request a replacement using our online web form.

Related Articles:
Operating systems that support exFAT
Deleting files on a memory card using a Mac
Deleting files on a Cruzer USB flash drive using a Mac

Disk Utility User Guide

In Disk Utility on Mac, you can erase and reformat storage devices to use with your Mac. Erasing a storage device deletes everything on it.

Format Flash Drive On Mac

If you have any files you want to save, copy them to another storage device.
Open the Disk Utility app on your Mac using one of the following methods, depending on the type of disk or volume you want to erase:
- If you want to erase your startup disk: Start up from macOS Recovery, then choose Disk Utility from the Recovery window.
- If you want to erase any other type of storage device: Double-click Disk Utility in the /Applications/Utilities folder.
Choose View > Show All Devices.
In the sidebar, select the storage device you want to erase, then click the Erase button .
Click the Scheme pop-up menu, then choose GUID Partition Map.
Click the Format pop-up menu, then choose a file system format.
Enter a name.
(Optional) If available, click Security Options, use the slider to choose how many times to write over the erased data, then click OK.
Secure erase options are available only for some types of storage devices. If the Security Options button is not available, Disk Utility cannot perform a secure erase on the storage device.
Click Erase, then click Done.

Note: With a solid-state drive (SSD), secure erase options are not available in Disk Utility. For more security, consider turning on FileVault encryption when you start using your SSD drive.

Format Flash Drive On Macbook Air

See alsoPartition a physical disk in Disk Utility on MacFile system formats available in Disk Utility on MacPartition schemes available in Disk Utility on MacFormat a disk for Windows computers in Disk Utility on MacApple Support article: How to erase a disk for Mac