What RAM cache is and why clearing it helps

RAM cache is temporary data your computer stores in its fastest memory to speed up repeated tasks. When you open a program, visit a website, or load a file, Windows or macOS saves pieces of it in RAM so the next time you need it, the computer doesn't have to fetch it from the slower hard drive. This is useful — until the cache grows so large that it leaves little room for new tasks, and your computer slows down.

Clearing the cache frees that space back up. Your computer will run the same programs and load the same files slightly slower the first time after clearing, because it has to rebuild the cache from scratch. But overall system speed usually improves because you've given active programs room to breathe. Most people notice the difference most when they have many browser tabs open, multiple applications running, or are working with large files.

Key Takeaways

  • RAM cache is temporary data stored in your computer's fastest memory; clearing it frees space for active programs.
  • Windows users can clear cache through Settings, Disk Cleanup, or by restarting — restarting is the safest method.
  • Mac users can restart their computer or use Terminal commands to clear cache without restarting.
  • Clearing browser cache separately (in Chrome, Firefox, Safari, or Edge) removes website data and can improve browsing speed.
  • You do not need third-party cleaning software; built-in tools work just as well and carry less risk.

Clearing cache on Windows by restarting

The simplest and safest way to clear RAM cache on Windows is to restart your computer. When Windows shuts down, it clears all data from RAM, including the cache. When it boots back up, the cache starts fresh and empty.

Click the Start button in the bottom left, then click the power icon. Select Restart. Let the computer fully shut down and boot back up — this usually takes two to five minutes. Once you're back at the desktop, your RAM cache is cleared. This method works on Windows 10 and Windows 11.

If you need to clear cache without restarting, you can use Disk Cleanup. Open the Start menu and type "Disk Cleanup" into the search box. Click the Disk Cleanup app. A window will open asking which drive to clean — select your main drive (usually C:). Check the boxes next to "Temporary files" and "Temporary internet files", then click Delete Files. This removes some cached data without restarting, though a restart clears more.

Clearing cache on Mac without restarting

Mac users can clear cache through Terminal, which is faster than restarting. Open Terminal by pressing Command + Space, typing "Terminal", and pressing Enter. A black window will open with a command prompt.

Type this command exactly as shown and press Enter: sudo purge. Your computer will ask for your password — type it and press Enter again. (The password won't appear as you type, which is normal.) The command runs silently and takes a few seconds. Your cache is now cleared. You can close Terminal.

If you prefer not to use Terminal, restarting your Mac also clears the cache completely. Click the Apple menu in the top left, select Restart, and let the computer shut down and boot back up.

Clearing browser cache in Chrome, Firefox, Safari, and Edge

Your web browser stores its own cache — copies of websites you've visited, images, cookies, and login information. Clearing this separately from system cache can speed up browsing and free additional space.

In Chrome: Click the three-dot menu in the top right. Select Settings, then Privacy and security, then Clear browsing data. Make sure "Cached images and files" is checked. Set the time range to "All time" if you want to clear everything, or "Last 7 days" for recent cache only. Click Clear data.

In Firefox: Click the hamburger menu (three horizontal lines) in the top right. Select Settings, then Privacy & Security. Under "Cookies and Site Data", click Clear Data. Check "Cached Web Content" and click Clear.

In Safari: Click Safari in the top menu bar, then Settings. Go to the Privacy tab, then click Manage Website Data. Click Remove All to clear all cached website data.

In Edge: Click the three-dot menu in the top right. Select Settings, then Privacy, search, and services. Under "Clear browsing data", click Choose what to clear. Check "Cached images and files" and click Clear now.

When to clear cache and what to expect

Clear your cache when your computer feels noticeably slower, when you have many programs open at once, or after you've been working for several days without restarting. You don't need to clear it daily — most computers run fine with cache building up over a week or two.

After clearing, your first few minutes of use may feel slightly slower as programs and websites reload from disk. This is temporary. By the time you've opened your usual programs and visited your regular websites, the cache rebuilds and speed returns to normal — usually within an hour of regular use.

Why you don't need cleaning software

Many third-party programs claim to clean your computer faster or more thoroughly than built-in tools. You don't need them. Windows Disk Cleanup, Mac's Terminal purge command, and browser settings do everything necessary to clear cache safely. Third-party cleaners sometimes remove files you actually need or slow down your computer with their own background processes.

Stick with the methods in this guide. They're free, built into your operating system, and carry no risk of removing something important by mistake.

Frequently Asked Questions

Will clearing cache delete my files or passwords?

System cache clearing (RAM or temporary files) does not touch your documents, photos, or saved passwords. Browser cache clearing removes saved passwords and login information for websites — you'll need to log back in. If you want to keep passwords, uncheck "Cookies and other site data" when clearing browser cache and clear only "Cached images and files".

How much space does cache actually take up?

System cache typically uses 500 MB to 2 GB depending on how long your computer has been running. Browser cache can range from 100 MB to 500 MB. The amount varies by how many programs you use and how many websites you visit. Clearing it won't free enormous amounts of space, but it does free RAM for active tasks, which improves speed.

Is it safe to clear cache while programs are open?

Yes, clearing system cache while programs are running is safe. Clearing browser cache while the browser is open is also safe — you may need to refresh open web pages to reload them. Restarting your computer is the safest method because it closes everything first, but it's not required.

Do I need to clear cache on my phone?

Phone cache works the same way as computer cache. You can clear it through Settings on both iPhone and Android. On iPhone, go to Settings > General > iPhone Storage and select apps to offload or delete. On Android, go to Settings > Apps, select an app, and tap "Clear Cache". Restarting your phone also clears cache, just like a computer.