Start by finding what's taking up the most room

Before you delete anything, you need to see which files and programs are actually using your storage. Windows and Mac both have built-in tools that show you exactly where your space is going — and most people are surprised to find that a handful of things account for the majority of what's full.

On Windows, open File Explorer, right-click on your C: drive (or whichever drive is full), and select Properties. You'll see a pie chart showing how much space is used. For more detail, read the free tool WizTree or TreeSize Free, which show you every folder and file ranked by size. On Mac, click the Apple menu, go to About This Mac, then Storage — you'll see categories like Photos, Applications, and Documents with their sizes.

Key Takeaways

  • Use your operating system's built-in storage tool or a free third-party program to identify which files and folders are consuming the most space before you start deleting.
  • Your Downloads folder, old backup files, and duplicate photos are usually the fastest places to recover gigabytes of space.
  • Uninstalling programs you no longer use frees up space and can improve your computer's speed.
  • Moving large files like videos or photo libraries to an external drive or cloud storage keeps them accessible without filling your main drive.
  • Clearing your browser cache and temporary files is safe and usually recovers several gigabytes with no risk to your work.

Empty your Downloads folder and temporary files

Your Downloads folder is often the single biggest space-waster on a computer. Most people read files and never organize or delete them — installers, PDFs, old email attachments, and images pile up for months or years. Open your Downloads folder, sort by date, and delete anything you no longer need. If you're unsure whether you need something, move it to a folder on your desktop first; if you don't touch it in a week, delete it.

Next, clear your temporary files. On Windows, press Windows key + R, type %temp%, and press Enter. Select all files (Ctrl+A) and delete them — Windows will skip any files currently in use. On Mac, open Finder, press Command + Shift + G, type /Library/Caches, and delete the contents. These are safe to remove; your computer recreates them as needed.

Uninstall programs you're not using

Every program installed on your computer takes up space, and many you haven't opened in months or years. On Windows, go to Settings > Apps > Apps & features, then scroll through the list. Click any program you don't use and select Uninstall. On Mac, open Applications in Finder, right-click a program, and select Move to Trash.

Be cautious with anything you're unsure about — if you don't recognize the name, search for it online before removing it. Some programs are part of your system or required by other software. If you're not certain, leave it alone. Focus on the obvious ones: old games, trial software, duplicate browsers, or programs you installed once and never used again.

Move large files to external storage or cloud backup

If you have large video files, photo libraries, or archived projects, moving them off your main drive is faster than deleting them and keeps them safe. External hard drives are inexpensive — a 1 or 2 terabyte drive costs $50 to $100 and can hold years of files. Plug it in, copy your large folders to it, and then delete the originals from your computer.

Cloud storage like Google Drive, OneDrive, or Dropbox also works, though it's slower for very large files. The advantage is that you can access your files from any device. Many people use both: keep recent work in cloud storage for access, and archive older projects to an external drive for long-term storage.

Clear your browser cache and temporary internet files

Your web browser stores copies of every webpage, image, and video you visit so pages load faster next time. Over months, this cache can grow to several gigabytes. On Chrome, Firefox, or Edge, press Ctrl + Shift + Delete (Windows) or Command + Shift + Delete (Mac) to open the cache-clearing menu. Select All time for the date range, check Cached images and files, and click Clear data. This is completely safe — it only removes temporary copies, not your bookmarks or saved passwords.

If you use Safari on Mac, go to Safari > Settings, click Privacy, then Manage Website Data. Select all and click Remove.

Delete duplicate and old backup files

Many computers accumulate duplicate files without you realizing it. If you've ever copied a folder, saved multiple versions of a document, or synced files between devices, you likely have copies taking up space. Search your computer for files with names like "Copy of" or version numbers like "Document_v1", "Document_v2", and so on. Keep the most recent version and delete the rest.

Check your backup folders too. If you've upgraded your computer or switched devices, old backup files may still be sitting on your drive. On Windows, look in C:\Users\[Your Name]\AppData for old backup folders. On Mac, check ~/Library for old Time Machine or migration assistant files. These are safe to delete if you've already migrated to a new computer.

Use Disk Cleanup or Storage Sense for automatic removal

Windows includes a built-in tool called Storage Sense that can automatically delete temporary files and old downloads. Go to Settings > System > Storage, then turn on Storage Sense. You can set it to run automatically and choose how old files need to be before deletion — for example, delete downloads older than 30 days, or temporary files older than 7 days.

Mac users can enable Optimize Storage in System Settings > General > Storage. This automatically removes old files and moves infrequently used programs to cloud storage. Both tools are safe and designed specifically to remove files you're unlikely to need.

When to call for help

If your computer is still full after trying these steps, or if you're uncomfortable deleting files, a local computer repair shop can help. They can identify what's taking up space and safely remove it without risking your important files.

If your drive is physically failing or making unusual sounds, stop using it and take it to a professional — continuing to use a failing drive can result in permanent data loss. A technician can determine whether the drive can be recovered or needs replacement.

Frequently Asked Questions

Is it safe to delete files from the Temp folder?

Yes. The Temp folder holds temporary files your computer creates while running programs. Deleting them is safe — your computer will recreate any it needs. If a file is currently in use, Windows will skip it automatically.

What if I delete something important by accident?

If you deleted a file recently, check your Recycle Bin (Windows) or Trash (Mac) — files stay there for a while before permanent deletion. If it's been longer, recovery software like Recuva (Windows) or EaseUS Data Recovery (Mac) can sometimes restore deleted files, though success depends on how long ago the file was deleted and what you've done since.

Should I delete my browser history to free up space?

Browser history takes up very little space — usually just a few megabytes. Clearing your cache (temporary copies of webpages) frees up much more. You can clear cache without deleting history if you want to keep your browsing record.

Can I move my entire Documents or Pictures folder to an external drive?

Yes, but do it carefully. Copy the folder to your external drive first, verify the files are there, and only then delete the original. Moving system folders (like Desktop or Documents) can sometimes cause programs to stop working correctly, so it's safer to move only specific subfolders or file types.

How much free space should I keep on my computer?

Aim to keep at least 10 to 15 percent of your drive free. If your drive is nearly full, your computer slows down because it can't create temporary files while running programs. Once you free up space, you should notice your computer runs faster.