Start with the easiest wins: temporary files and the recycle bin

Your computer collects junk files automatically as you work—temporary internet files, old installer programs, and fragments left behind when you uninstall software. Clearing these out is the fastest way to free up storage space and can improve how quickly your computer runs.

On Windows, open the Disk Cleanup tool by typing "Disk Cleanup" into the search box at the bottom left of your screen. Select your main drive (usually C:), and the tool will scan for temporary files. Check the boxes next to "Temporary files," "Recycle Bin," and "Temporary internet files," then click Delete. This usually frees up several gigabytes without touching anything you need.

On Mac, open Finder, click Applications, then Utilities, and launch Disk Utility. Select your hard drive and click "Empty Trash" from the menu. For a deeper clean, you can also go to Library (hold Option while clicking Go in the menu bar) and delete the Caches folder—but only if you are comfortable with the fact that some programs will rebuild their cache files the next time you use them.

Key Takeaways

  • Temporary files, old installers, and browser cache take up gigabytes of space and can be deleted safely using built-in Windows or Mac tools.
  • Large files you no longer need—old videos, duplicate photos, or archived projects—often occupy far more space than temporary junk and should be moved to external storage or deleted.
  • Uninstalling programs you no longer use removes both the program files and the registry entries or preference files that slow down your system.
  • Disabling startup programs that run automatically when your computer boots can noticeably improve startup speed without deleting anything.
  • Running a malware scan with Windows Defender or a third-party tool can identify and remove unwanted programs that consume resources.

Find and delete large files taking up the most space

Before you spend time on small cleanups, locate the files actually consuming your storage. On Windows, right-click your C: drive, select Properties, and look at the pie chart showing what is using space. Then open File Explorer, right-click C: again, and choose "Analyze disk space" (or use the free tool WinDirStat, which shows a visual map of what is taking up room).

On Mac, click the Apple menu, select About This Mac, then Storage. You will see a breakdown by category. Click the category using the most space—usually Photos or Documents—and sort by file size to find the largest items. You can also use the free tool Disk Diag to see exactly which folders are largest.

Once you identify large files, decide what to keep. Old video projects, downloaded installers, and duplicate photos are common culprits. Move files you might need later to an external hard drive or cloud storage (Google Drive, OneDrive, or iCloud all offer free tiers). Delete the rest. This single step often frees up 20 to 50 gigabytes or more.

Uninstall programs you no longer use

Every program installed on your computer takes up disk space and can slow down startup time. On Windows, go to Settings, click Apps, then Apps & Features. Scroll through the list and click any program you do not recognize or no longer use, then select Uninstall. Follow the prompts to remove it completely.

On Mac, open Applications in Finder and drag unused programs to the Trash, then empty the Trash. Some programs leave behind preference files in the Library folder, but for most everyday software, dragging to Trash is sufficient. If you want to be thorough, you can use the free tool AppCleaner, which removes both the program and its associated files.

Pay special attention to programs that came pre-installed on your computer. Many computers ship with trial versions of antivirus software, office suites, or games that you may never use. Removing these can free up several gigabytes and reduce the number of programs competing for your computer's attention when it starts up.

Disable programs that run at startup

Many programs are set to launch automatically when your computer starts, even if you rarely use them. This slows down boot time and consumes memory while they run in the background. On Windows, right-click the taskbar at the bottom of the screen and select Task Manager. Click the Startup tab to see which programs launch automatically.

Look through the list and right-click any program you do not need running all the time—cloud storage apps, messaging programs, or software updaters are common examples. Select Disable. The program will still be installed and you can open it manually whenever you need it, but it will no longer slow down your startup.

On Mac, go to System Settings, click General, then Login Items. You will see a list of programs that open when you log in. Select any you do not need and click the minus button to remove them from startup. This change takes effect the next time you restart.

Run a malware scan to remove unwanted programs

Sometimes your computer accumulates programs you did not intentionally install—adware, browser toolbars, or other unwanted software that consumes resources and slows performance. Windows Defender, built into Windows 10 and 11, can find and remove these. Open Windows Security (search for it in the Start menu), click Virus & threat protection, then click Scan options and select Full scan.

On Mac, malware is less common, but you can still scan using the built-in XProtect by going to System Settings, Privacy & Security, and checking that File Quarantine is enabled. For a more thorough scan, the free tool Malwarebytes for Mac can identify and remove unwanted programs.

If Windows Defender or your antivirus tool finds threats, follow the prompts to quarantine or remove them. After the scan completes, restart your computer. You may notice a significant improvement in speed if unwanted programs were running in the background.

Clear your browser cache and remove unused extensions

Your web browser stores copies of every webpage you visit, along with images and scripts, to load pages faster next time. Over months or years, this cache can grow to several gigabytes. In Chrome or Edge, click the menu (three dots), go to Settings, then Privacy and security, and select Clear browsing data. Choose All time, check Cached images and files, and click Clear data.

In Firefox, click the menu (three horizontal lines), go to Settings, then Privacy & History, and click Clear Data. In Safari on Mac, click Safari in the menu bar, then Settings, then Privacy, and click Manage Website Data to see what is stored.

While you are in your browser settings, also review your extensions—small programs that add features to your browser. Each one consumes memory and can slow down page loading. Click the extensions icon (usually a puzzle piece) and remove any you no longer use. Keep only the ones you actively rely on.

Update your operating system and drivers

Outdated software can cause your computer to run slowly or use more storage than necessary. Windows and Mac both release regular updates that improve performance and fix bugs. On Windows, go to Settings, click Update & Security, and select Check for updates. Install any available updates and restart your computer when prompted.

On Mac, click the Apple menu, go to System Settings, then General, and click Software Update. Install any available updates. You can also enable automatic updates so your computer stays current without you having to check manually.

Outdated device drivers—software that lets Windows or Mac communicate with your hardware—can also slow performance. On Windows, right-click the Start button, select Device Manager, and look for any devices with a yellow warning icon. Right-click those devices and select Update driver. On Mac, drivers usually update automatically with system updates, so there is no separate step needed.

Frequently Asked Questions

Is it safe to delete files from the Temp folder?

Yes. The Temp folder holds temporary files created by programs while they run, and these files are meant to be deleted. On Windows, you can safely delete everything in C:\Users\[Your Username]\AppData\Local\Temp. On Mac, the equivalent is /var/tmp and /tmp. If a program is actively using a temp file, Windows or Mac will prevent you from deleting it, so you cannot accidentally break anything by trying.

Will cleaning up my computer make it faster?

Removing temporary files and large unused files frees up storage space, which can help if your drive is nearly full. Disabling startup programs and removing malware will noticeably improve boot time and overall responsiveness. However, if your computer is old or has very little RAM, cleaning alone may not make a dramatic difference—hardware upgrades or a fresh operating system installation may be necessary.

How often should I clean up my computer?

Running Disk Cleanup or clearing browser cache once a month is a reasonable routine. Uninstalling programs you no longer use can happen as needed. If you notice your computer slowing down, run a malware scan and check your startup programs before assuming you need a major cleanup.

What should I do if I accidentally delete something important?

If you deleted a file by mistake, check your Recycle Bin (Windows) or Trash (Mac) first—files stay there for a while before being permanently removed. Right-click the file and select Restore. If the Recycle Bin or Trash has been emptied, recovery is much harder. For this reason, always back up important files to external storage or cloud storage before doing a major cleanup.

Do I need third-party cleaning software?

No. Windows and Mac both include built-in tools (Disk Cleanup, Disk Utility, Task Manager, and Windows Defender) that handle the most common cleanup tasks. Third-party tools like CCleaner or CleanMyMac can automate some steps, but they are not necessary and some charge a subscription fee. The built-in tools are free and sufficient for most users.