When you’ve been struggling with formatting your Mac or MacBook Pro’s SSD it’s so frustrating.
Take a breath and read through the quick solutions to try in this article.
Here is my checklist of what I do when I can’t format my SSD on Mac. And get my formatting done.
Unable To Format SSD Mac Solutions
1. Are You Clicking On Your SSD In The Right Place In Disk Utility?
To solve your can’t format SSD Mac issue. And this is one that catches a lot of people out.
Click on your SSD at the right level in Disk Utility, your Mac’s disk management software. It’s crucial to getting your drive formatted. By default, Disk Utility only shows one level. It shows only volumes when you first open Disk Utility.
But you need to see all devices.
This solution also works when your formatting an Internal SSD drive. And have booted to MacOS Recovery Mode to use Disk Utility to format.
When you check under the External heading in Disk Utility. And only see the one entry there for your external SSD. Or internal SSD and Disk Utility looks similar to the picture below.
Disk Utility only shows the one entry.
What you’re looking for is Disk Utility to show you more. As in this picture.
You change your Disk Utility view.
With your Disk Utility window open look at the top of your Mac’s desktop. Pick the View option. And change the setting to Show All Devices.
You should click the arrow to the left of your SSD to expand the view.
When you can see all the levels.
Then click on your SSD’s name at the top level. Right where it’s listed under the External heading. You do this before clicking on Erase to set up your formatting options. Before formatting your SSD drive.
2. Can You See Another External Device On Your Mac?
If your issue is you can’t see your SSD at all in Disk Utility to format on your Mac. Then do a bit of testing.
Plug in a flash drive, or thumb drive into that same Mac USB port. Does that flash drive shows up in Disk Utility? If it does then.
3. Plug Into Another USB port on your Mac.
Plugging into another USB port on your Mac can solve your SSD not formatting on your Mac.
Because when you’ve plugged in and out a lot of different USB devices. The software in Mac OS sitting on the USB port. Waiting for the next device to be plugged into that port gets hung up and does nothing.
You plugging into another port, by passes that hung software. Giving you the result you need to format your SSD with success.
4. Shutdown, Wait and Reboot Your Mac.
When you can’t format an SSD the next thing to do is reboot your Mac.
You may have simply put your Mac to sleep when you’ve done using it. And that’s fine. But over time your Mac could get to the stage where it just needs a full power down and power back up.
This then resets your Mac software and the registries of your Mac.
So, shutdown your Mac.
Go to the top left of your desktop. Click on the Apple logo for your Apple menu and pick Shutdown.
After you’ve shutdown. Wait more than 10 seconds and then power back on.
5. Check The USB Cable Connections To Your SSD.
You being unable to format SSD’s can come down to something as silly and basic as a failed. Or incompatible cable.
USB cables fray and can break inside over months of use.
Or you may have an incompatible cable between your Mac and your SSD USB drive.
Try the cable on another external drive if you have one.
Does the USB cable work.
There are reports on the Web of certain solid state drives not working on the latest Mac’s with the cable supplied. But have worked when used with the USB cable supplied with their Mac.
It’s not been an experience I’ve had with my Mac. But if a simple cable swap sorts your difficulties with formatting, then give it a try. And see if your solid state drive formatting works then?
6. Will Your SSD Format On Another Mac.
An SSD not formatting could well be an issue with your SSD. It’s a good idea to see if your SSD will run and be formatted by another Mac.
There are some reports of issues formatting SSD’s using Mac OS Monterey. And success formatting the SSD with Big Sur. That’s not been my experience but I wouldn’t discount it. It’s possible that the software stack you’re running on your Mac may cause a conflict when formatting your SSD.
So put your SSD on a Mac running an earlier Mac operating system release, if that’s an option for you. And once your drive is formatted then you can use on your own Mac.
7. Disk Utility First Aid.
Your unable to format an SSD could mean disk errors or bad blocks on your SSD. Disk Utility, your Mac’s disk management software as part of it has First Aid.
First Aid will check your drive and repair the SSD disk errors and bad sectors it finds.
Before you can run First Aid check you can see all the levels of your drive.
At the top of your open Disk Utility window pick the View option. then pick Show All Devices.
Expand the list so you can see all the levels of your SSD external drive. Then click on your drive at the top level.
This is important because First Aid won’t run if you’ve not clicked on your drive at the top level.
Then pick First Aid. You Mac will ask you to confirm you want to run First Aid on your SSD drive.
If First Aid doesn’t run for you the first time. And this has happened to me. Just eject your SSD USB drive. Plug back in and rerun First Aid.
It could be you need to plug into a different USB port. That’s often worked for me when First Aid hasn’t run the first time.
8. Can’t Format SSD Because Disk Utility Is Taking A Long Time
And this can make you think you can’t format your SSD.
Your SSD is plugged in. You’ve clicked your drive at the right level before setting your format options. But when you click erase. Instead of your drive formatting in moments. It takes ages.
Disk Utility runs a check on your SSD ahead of formatting and writing a file system. Most of the time this check takes seconds and then your SSD is formatted. But when Disk Utility finds an issue it’ll do what it can to repair the issue.
This can take quite a while. Sometimes overnight. Leave your Mac to sort your drive overnight and see if all’s well in the morning. If not, and you’ve tried all the options so far listed in this article. Then you’ve a more serious issue with your solid state drive.
9. Unable To Format SSD Mac As APFS (Apple File System).
When you can’t format external SSD as APFS. Because the APFS (Apple File System) option hasn’t come up in the format options. Or your Mac just won’t.
Then format your external SSD as Mac OS Extended first. Use a GUID Partition Map for Scheme. Then run through the format steps a second time and then format as APFS.
We hope you enjoyed our article showing you the solutions when you’re unable to format your Mac’s SSD. Thank you for reading to the end. While you’re here … please check out our other recommended articles on this subject.
About Paul Gregory
I’ve been a system administrator for various corporates for 15 years. And as admin I’ve helped many with their Mac’s and there many Apple devices.
I’m excited by watching users, armed with a little knowledge take control of their Mac’s and their files. And why not?
When I’m not at work or working on the site I like to chill with few beers. And watch a bit of car racing. From Formula 1 to stock car racing. The competition is my thing.