You have your external hard drive or SSD drive in your hand. And you’re just about to format your external drive with Disk Utility on your Mac.
You’ve already decided that Mac OS Extended file system format is what you want.
You’ve noticed that you’ve the option of formatting as Mac OS Extended Journaled. Or Mac OS Extended (Journaled) case-sensitive.
So, which do you pick? And why would you pick one rather than the other.
Mac OS Extended Journaled VS Case Sensitive
Mac OS Extended Journaled is a Mac file system. Case-Sensitive is an option of that file system.
And as its name means it is sensitive to whether you use upper or lower case letters in your file name. Mac OS treats a file or folder with the name of photo, or Photo as separate files when in the same folder.
At A Glance Mac OS Extended Vs Mac OS Extended (Case-Sensitive)
|Mac OS Extended||Case-Sensitive|
|Sensitive To File Name Case||No||Yes|
|Optimized For HDD||Yes||Yes|
|Older Mac Support||Yes||Yes|
When Would You Pick Mac OS Extended Journaled Versus?
For the vast majority of Mac users. You’d simply pick Mac OS extended in Disk Utility when you’re formatting your external hard drive.
It’s the default file system version that is the most widely supported.
Macs running Mac OS Sierra or earlier only support MacOS Extended Journaled for its drives.
Later Mac OS X versions. Like Mojave, Catalina, Big Sur and Monterey have internal SSD drives with APFS (Apple File System) on them. But will equally read and happily use an external drive in MacOS Extended Journaled.
Plus, every Mac computer since 1998 supports Mac OS Extended on an external drive for a Mac Time Machine backup.
Extended Journaled (not case-sensitive) treats files called photo and PHOTO as the same. And asks to overwrite one with other when you save.
But for those files to hold different data in them. And Mac OS not ask to overwrite one file with the other. They would need to be in different folders.
Extended Journaled is happy for files to have the same file name. As long as those files live in different folders.
Versus When Would You Pick Mac OS Extended Case-Sensitive?
There are only rare edge cases where you’d pick a case sensitive version of OS X Extended.
You’d pick where you’ve a need for an external drive to be sensitive to the case used in file and folder names.
For example. Where what you’re doing on your Mac’s external USB drive needs your Mac to treat a file saved as Photo. As a different file from a file saved as photo in exactly the same folder.
Where you want folder names phoTo and pHoto to be two completely separate folders. One beside the other saved inside the same folder.
And most Mac users don’t need that feature.
The Drawback Of Using Case Sensitive VS Non Case-Sensitive File System
There are some distinct drawbacks in formatting your external drive in Disk Utility as a case sensitive file system.
Because most applications you’d run on your Mac computer. Including many of Apple’s own applications. Don’t recognize a case sensitive file system. And simply won’t work right.
On standard Mac OS Extended, your folder photo, Photo and PHOTO are in the same place on your external USB drive.
Most applications you’d run on your Mac including the Apple ones expect that. And so are delightfully case insensitive.
And if you’ve made the mistake of formatting your external hard drive. Or external SSD as case sensitive. Then realize your applications won’t work with a drive formatted that way.
The only way to change it is to reformat your drive with Disk Utility. And that means putting any files you have on the drive somewhere safe while you do that.
So that you can copy them back on after formatting.
A Bit Of Background: Mac OS Extended Case Sensitive Journaled Or Mac OS Extended
Both Mac OS Extended Journaled case sensitive. And Mac OS Extended Journaled are at their core the same file system.
They both are Journaled file systems. And the original file system formats on a Mac. created by Apple Inc. back in 1998.
You’ll also see Mac OS Extended referred to as HFS+ (HFS Plus).
Mac OS Extended was the default file system on a Mac. And used for a Mac’s internal drives and external drives.
The file systems equally support the use of and saving of large files (above 4GB). And as Mac file systems an external drive can be formatted in either file system format by Disk Utility.
And that external drive will be recognized by another Mac.
But can’t be seen by a Windows PC. Not without the use of a 3rd party software solution. Called driver software.
With driver software installed. A Windows PC can view a Mac OS Extended journaled file system on that Windows computer.
A Drive As Extended Journaled Or Case Sensitive
You easily create either Mac format using Disk Utility on your Mac. OS Extended file system or OS Extended Journaled Case-Sensitive.
Although Mac OS Journaled was created at a time when a mechanical drive was the only option you had for an external drive. So, you could say it’s optimized for hard drives. Hard drives are called mechanical drives because they have moving parts inside.
You can equally use both formats on an external SSD drive.
Other Versions Of OS Extended And Case-Sensitive
Mac OS Extended has other options you’ll see in Disk Utility. There is an encrypted version where you can secure your files by adding a password.
Then no one can look at the files on your drive without entering that password.
And there is a case-sensitive and encrypted version. Where the file system is not only sensitive to the upper and lower case use in the file system. The drive is also protected by a password.
You may well want to protect your files from prying eyes. If you do pick the version of Mac OS Extended with encryption in Disk Utility.
It would be rare for a user to pick not only case sensitive, but add encrypted as well. The need for that Mac format is a true edge case.
Both the encrypted and case sensitive and encrypted versions for Mac OS Extended are only available in Mac OS 10.12 (Sierra) or earlier releases.
Extended Journaled VS Case-Sensitive FAQ
What Is MacOS Case Sensitive Journaled
MacOS Case Sensitive Journaled is a version of Mac OS Extended (Journaled) file system. It’s a version of MacOS Journaled that is sensitive to the case you use in naming files that are in the same folder.
And treats the files PHOTO and photo as different files. With different data inside them. To open the file PHOTO you’d have the type the file name as it’s stored on the drive. Matching the letter case you used to save the file exactly.
So, now you know the difference between the two. The case-sensitive version of MacOS Extended and the version normally used. – Simply MacOS Extended Journaled.
Picking to format your external drive as case-sensitive would be rare. And only if you were sure.
You’d need the application you planned to use, to support the case-sensitive version of the operating system file format.
While you are here do take a look at our other related articles about the different file system formats on a Mac.
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.