SSDs and hard drives - even high-capacity disks - can fill up fast these days. If your computer is telling you that your hard drive is full, then we can help you to free up disk space in Windows 10 and older versions.

Disk Clean-up

Windows has several built-in tools which will automatically find and delete unnecessary files to free up disk space. 

The first to try is Disk Clean-up. Simply search for it in the Start menu. This will scan your PC an highlight space used by temporary files, downloaded updates, cached files and files in the Recycle Bin. You can tick the boxes to delete some or all of the files. 

How to free up disk space on Windows 10

You have to click the Clean up system files button to do a deeper scan (you have to select the particular drive - usually C: - to check for system files). This will let you delete old versions of Windows which could be using up scores of gigabytes. 

Uninstall games and apps

A relatively quick and easy way to free up space is to uninstall programs you don't need or use. From the Start menu search for Control Panel and then look for 'Uninstall a program'. Click on this and you'll see a list of everything installed and you can rearrange the list by clicking on 'Size' to order it so the programs taking up the most space are at the top.

Typically these will be games, but some applications can also use multiple gigabytes. You have to remove them one by one, and it can take a while, but it can free up an awful lot of disk space.

How to free up disk space on Windows 10

There are certain uninstaller programs you can download which can remove multiple programs in one go. For more, see Best uninstaller programs for Windows.

Note that you shouldn't delete some large files as they're critical to Windows' operation. One is hiberfil.sys.

Restore points

Windows creates restore points automatically so you can roll back to a previous state if something goes wrong after you install a new driver or program. This uses up disk space, but you can adjust how much space System Restore uses.

To do this, search the Start menu for System Restore, then click on it when it appears. It will bring up the System Properties windows on the System Protection tab. Click the Configure... button to see and change how much space this tool uses. It's unwise to disable system protection as you'll have no restore points should anything go wrong.

How to free up disk space on Windows 10

Delete driver downloads, duplicate files and more

Beyond Windows' own tools, you can download a plethora of utilities which can do a more thorough search, finding and deleting even more unnecessary files. Ccleaner is a good place to start, as it's free, but there are also others which can find duplicate files (such as photos and downloads) and remove the surplus copies. One is Auslogics Duplicate File Finder, but there are many others.

How to free up disk space on Windows 10

How to find large files on your hard drive

If you've followed the advice above, but don't know where else to look, you can find the biggest individual files on your hard drive by opening File Explorer (Windows Explorer in previous versions) and typing ‘size:gigantic’ into the search bar.

This will bring up a list of any fine over 128MB in size, which you can then look through to find large files such as downloads, outdated drivers, backups and ISO images. However, always be careful and make sure you know exactly what it is your deleting, as some files could stop certain programs from running if removed.

How to free up disk space on Windows 10

Of course, sometimes it’s not large individual files that take up room, but rather folders full of lots of small files. In this case, the best option is to download a small third-party program that scans your computer to inform you which files and folders are the biggest offenders.

Our favourite application for this task is the free program, SpaceSniffer. It doesn't require installation, so just run the program and it will scan your chosen HDD, and then visually display your disk information using rectangular boxes; the bigger the box, the bigger the file or folder. You can also customize the view to show more detail, or double-click each box to expand it and find out which files or folders within that box are taking up the most space.

Once you've ascertained which files and folders are taking up excess space on your disk, you can delete the ones you no longer need using File Explorer.

How to free up disk space on Windows 10

Delete backups

Another way to reclaim disk space is to check for backups. If you use backup software, use the software (or check in the folder where it stores files) to delete old versions you no longer need. 

The same goes for iPhone and iPad backups. These can create enormous files which can hog hundreds of gigabytes. Open iTunes, click the tiny drop-down menu at the top left, choose Preferences, then click on Devices. You will see a list of backups, although not how much space they're occupying. Aim to keep only the most recent one for each device, but if you find even these are taking up too much space, delete them and make a fresh backup from your device.

Another place to check is your Videos folder, and any on-demand video software such as BBC iPlayer. Delete downloaded videos you don't need, and copy personal videos to an external hard drive.

You might also like to read: How to recover deleted files for free.