How to Check Free Hard Drive Space in Windows

You can't just add stuff to a drive forever, be it your main hard drive, the little flash drive in your pocket, or the giant external hard drive on your desk.

Even an arguably humongous 16 TB hard disk has a limit: 16 TB! As crazy as it sounds, it, too, can fill up. True, it'll take two million high-quality photos to do it, but "only" about 150 feature-length 4K movies.

How to Check Free Hard Drive Space in Windows

It takes only a minute or two to check how much storage you have on any of your drives, and it's especially easy to do when you use File Explorer.

1. In Windows 11 or Windows 10, select the Start button, followed by File Explorer (the small folder icon). If you don't see it, check under the All apps or Windows System folder, or type file explorer into the search box.

   In Windows 8 or Windows 10, search for and then select This PC.

   In Windows 7 or Windows Vista, select the Start button, followed by Computer.

   In Windows XP, go to Start and then My Computer.

   Learn what version of Windows you have if you're unsure.

2. On the left-hand side of the window that's now open, make sure This PC, Computer, or My Computer is selected (the name depends on your version of Windows).

   If you don't see anything on the left side of this screen, open the View menu and enable the Navigation pane. In older versions of Windows, go instead to Organize > Layout > Navigation Pane (7 and Vista), or View > Explorer Bar > Folders (XP).

3. On the right-hand side, find the drive on which you want to know how much free space is left.

   In Windows 11/10/8, all storage devices are listed in the Devices and drives area. In Windows 7/Vista/XP, Hard Disk Drives and Devices with Removable Storage are listed separately.

4. In newer versions of Windows, you can see right under the drive listing how much free space is left on it, as well as the total size of the drive, in a format like this:

   Local Disk (C:)
   [storage space indicator]
   611 GB free of 931 GB
   

   If that's all you need to know then you're done! However, there is a bit more information about your drive's capacity buried just a bit deeper:

   Disk Savvy v15 Review

5. To see more, right-click or tap-and-hold the drive in question, and then choose Properties.

6. In the General tab, you'll see all the important details about the storage device you're looking at, reported in bytes as well as rounded GB.

   • Used space is the sum total of every piece of data on this device.
   • Free space is the difference in the total formatted capacity of the device and the sum total of every piece of data being stored on it. This number indicates how much more storage you're allowed to fill.
   • Capacity is the total formatted capacity of the drive.
   • The pie graph shows used vs free space on the drive, helpful for visualizing how much space you're using on this device.

You should now know exactly how much hard drive space is available on your computer. If you're running low, delete files you don't need or move them to a different hard drive that has more free space.

How to Check Free Hard Drive Space Using Command Prompt

Another way to check free space is with Command Prompt. The results aren't as easy to read because the values are represented in bytes instead of gigabytes, but it's still possible with this command:

wmic logicaldisk get size,freespace,caption

Performance Suffers on a Full Hard Drive

You may need to check the free space on a drive from time to time, especially if it starts to slow down or act funny, which is very often the not-so-clear consequence of too much stuff in a single place.

If unaddressed, extremely low disk space can result in strange behavior, cryptic error messages, or serious problems like a Blue Screen of Death (BSOD).

How Much Free Space Do You Need?

Microsoft has historically recommended that to avoid problems, you should leave at least 100 MB of free space on whatever drive you have Windows installed on. However, I've seen issues at levels higher than 100 MB, so I always recommended 10 percent free space instead.

Of course, in some cases, you might need far more free storage than that. For example, if you're copying a bunch of home movies to your computer or downloading a huge video game. In these situations, check how much storage those items are using before you put them on your computer to know how much space you need.

Calculate 10 Percent Free Space on Windows PC

To calculate 10 percent free space, just take the number next to Capacity from Step 6 and move the decimal to the left one space. For example, if the hard drive you're viewing has a total capacity of 250.0 GB, moving the decimal one space to the left makes it 25.0 GB, meaning that you shouldn't let the free space drop below that for that particular device.

Examine Types of Files Taking Up Storage Space

In Windows 11 & 10, much more detail about what sorts of files are using up your drive's capacity can be found in Settings > System > Storage. Just choose a drive you're interested in and Windows will analyze it, breaking it down into categories like System & reserved, Temporary files, Pictures, and more. These versions of Windows also support Storage Sense, a feature that can automatically free up space.

There are also several free disk space analyzer tools that'll show you which files and folders are occupying the most space.

In any version of Windows, choosing Disk Cleanup from the drive's properties (Step 6 above) will start the Disk Cleanup utility, a one-stop-shop for removing files that are no longer needed by Windows.