Check your hard drive space in three clicks on Windows or Mac

On Windows, right-click the drive you want to check in File Explorer, select Properties, and look at the pie chart near the bottom. The chart shows how much space is used (in blue) and how much is free (in white). The total capacity and free space appear in text below the chart.

On Mac, click the Apple menu, select About This Mac, then click the Storage tab. A horizontal bar shows your drive broken into colored sections — each color represents a different type of file (Applications, Documents, Photos, and so on). The total capacity and available space appear at the bottom of the window.

Both methods take less than a minute and show you exactly what you have room for. If your drive is nearly full, the sections below explain what that means and what to do about it.

Key Takeaways

  • Windows shows free space in File Explorer Properties; Mac shows it in About This Mac under the Storage tab.
  • A drive that is more than 90 percent full can slow down your computer because the operating system needs some empty space to work.
  • Photos, videos, and old backups usually take up the most room and are safe to delete if you have copies elsewhere.
  • External drives and cloud storage let you move files off your main drive without losing them.

Why hard drive space matters

Your computer needs empty space on the drive to run smoothly. When a drive gets very full — usually above 90 percent capacity — Windows and Mac slow down because they cannot write temporary files or cache data efficiently. Programs may freeze, startup times increase, and updates may fail to install.

Empty space also matters for how long your drive lasts. Solid-state drives (SSDs), which are in most newer computers, wear out faster when they are constantly full because the drive has to work harder to find space for new files. Keeping at least 10 to 20 percent of your drive empty extends its lifespan.

What takes up the most space on your drive

On Windows, use the built-in Storage Sense tool to see what is using space. Open Settings, go to System, then Storage. Windows shows a breakdown by category — Apps & features, Photos, Videos, Documents, and so on — with the size of each. Click any category to see individual files and delete the ones you no longer need.

On Mac, the Storage tab in About This Mac shows the same breakdown visually. Hover over each colored section to see what type of file it represents. For more detail, use a free tool like Disk Diag or DiskSight, which show you exactly which folders and files are largest. These tools help you spot old backups, duplicate photos, or downloads you forgot about.

Photos and videos are almost always the biggest space users. A single 4K video can be several gigabytes. Old backups, duplicate files, and large application caches come next. Once you know what is taking up room, you can decide what to delete or move.

How to free up space without deleting files

An external hard drive or USB flash drive lets you move files off your main drive and keep them safe. A 1 or 2 terabyte external drive costs $50 to $100 and plugs into any USB port. On Windows, right-click the files you want to move, select Cut, open the external drive in File Explorer, and select Paste. On Mac, drag files to the external drive in Finder. Once the files are copied, delete them from your main drive.

Cloud storage services like Google Drive, OneDrive, or iCloud also move files off your drive. These services store files on remote servers and let you access them from any device. Google Drive and OneDrive offer free plans with 15 gigabytes and 5 gigabytes respectively. iCloud is built into Mac and offers 5 gigabytes free, with paid plans starting at $0.99 per month for 50 gigabytes. Upload photos, documents, or old projects to the cloud, then delete the local copies from your drive.

Safe files to delete when space is tight

Downloads folder: Most files here are installers or documents you no longer need. Open your Downloads folder, sort by date, and delete anything older than a few months. Keep only installers for software you still use.

Temporary files and cache: Windows and Mac create temporary files while you work. On Windows, use Disk Cleanup (search for it in the Start menu) to remove these safely. On Mac, use a free tool like CleanMyMac X or Onyx. These tools delete cache files that your computer can rebuild if needed.

Duplicate photos: If you have backed up photos to the cloud or an external drive, you can delete the copies on your main drive. Use a tool like Gemini Photos (Mac) or Duplicate Photo Cleaner (Windows) to find and remove duplicates automatically.

Old backups: If you have Time Machine backups on an external drive (Mac) or File History backups (Windows), older backups take up space. Keep the most recent backup and delete older ones if space is tight.

When to upgrade your drive

If you regularly run out of space even after deleting files, your drive is too small for how you work. Upgrading means replacing your current drive with a larger one or adding a second drive. On a Mac, you can replace the internal SSD with a larger one (usually 500 gigabytes to 2 terabytes). On Windows, you can add an external SSD or replace the internal drive if your computer allows it.

Before upgrading, back up all your files to an external drive or cloud storage. Then either clone your current drive to the new one (so everything transfers automatically) or do a fresh install of your operating system and restore files from backup. If you are not comfortable opening your computer, a repair shop can do this for $50 to $150.

Frequently Asked Questions

How much free space should I keep on my hard drive?

Keep at least 10 to 20 percent of your drive empty. On a 500 gigabyte drive, that means 50 to 100 gigabytes free. If your drive is under 10 percent free, your computer will slow down noticeably and updates may fail.

What does "used space" mean?

Used space is everything stored on your drive: your operating system, programs, photos, documents, videos, and temporary files. It includes files you deleted but that are still in the Recycle Bin (Windows) or Trash (Mac) — emptying the trash frees up that space.

Can I check hard drive space on my phone or tablet?

Yes. On iPhone or iPad, go to Settings, tap General, then iPhone Storage (or iPad Storage). On Android, open Settings, tap Storage or About Phone, then Storage. Both show a breakdown of what is using space and let you delete apps and files directly.

Is it safe to delete files from the Windows temp folder?

Yes, but use Disk Cleanup or Settings > Storage instead of manually deleting from the temp folder. These tools know which temporary files are safe to remove. Manually deleting from the temp folder can sometimes remove files a program still needs.

What is the difference between storage and RAM?

Storage (your hard drive) holds files permanently — photos, documents, programs. RAM is temporary memory your computer uses while running programs. They are separate. A full hard drive slows your computer; low RAM makes programs freeze. Checking hard drive space does not tell you about RAM.