What cache is and why clearing it helps

Cache is temporary data your computer stores to make things faster. When you visit a website, your browser saves images, scripts, and page layouts so it doesn't have to read them again the next time you visit. Your operating system does the same thing — it stores pieces of recently used programs and files in memory so they load quicker. This is useful until it isn't: old cache can slow things down, take up disk space, or cause a website to show you outdated information instead of what's actually there now.

Clearing cache won't break anything. You're just telling your computer to forget these temporary copies and read fresh ones next time. The trade-off is that some things will load slightly slower the first time after you clear, because your computer has to fetch everything from scratch. For most people, that brief slowdown is worth it — especially if your computer has been running slowly or a website is behaving strangely.

Key Takeaways

  • Browser cache lives in your browser settings and stores website data; clearing it takes two to three minutes and won't delete your passwords or bookmarks.
  • Windows temporary files accumulate in a folder called Temp and can be cleared through Disk Cleanup or by deleting the folder manually.
  • DNS cache stores website addresses your computer has looked up recently; flushing it can fix problems where a website won't load even though it's actually online.
  • You can clear cache on a schedule (weekly or monthly) or only when you notice your computer slowing down or a website acting strange.

Clearing browser cache in Chrome, Firefox, and Edge

Most people's cache problem is in their web browser. Open the browser you use most, then use this keyboard shortcut: Ctrl + Shift + Delete (on Windows). This opens the "Clear browsing data" window directly.

In Chrome and Edge, you'll see a dropdown that says "All time" — leave it there. Check the boxes next to "Cookies and other site data" and "Cached images and files". Uncheck everything else unless you specifically want to delete your browsing history. Click "Clear data" and wait a few seconds. In Firefox, the same shortcut opens a similar window; select "Everything" from the dropdown, check "Cache", and click "Clear Now".

This clears only that one browser. If you use multiple browsers (Chrome and Firefox, for example), you need to repeat the process in each one. Clearing cache will not delete your saved passwords, bookmarks, or autofill information — those are stored separately and you have to specifically check those boxes to remove them.

Clearing Windows temporary files

Windows stores temporary files in a folder called Temp, and these can pile up over months and take gigabytes of space. The safest way to clear them is through Disk Cleanup, a built-in Windows tool. Press the Windows key, type "Disk Cleanup", and open it. Select your C: drive (or whichever drive Windows is installed on) and click OK. Windows will scan for temporary files.

In the window that appears, check the boxes next to "Temporary files" and "Recycle Bin". Do not check "Windows Update Cleanup" unless you know what you're doing — that one can cause problems if Windows needs to roll back an update. Click "Clean up system files" and then "Delete Files". This usually frees up between 500 MB and 2 GB, depending on how long it's been since you last cleared.

If Disk Cleanup doesn't appear or you want to do this manually, you can navigate directly to the Temp folder. Press Windows key + R, type %temp%, and press Enter. A folder will open. Select all files (Ctrl + A), delete them, and ignore any error messages about files that are in use — Windows will skip those and delete the rest.

Flushing DNS cache to fix website loading problems

DNS cache is different from browser cache. It's a list of website addresses (like google.com) and their actual computer locations (IP addresses) that your computer has looked up recently. Usually this is invisible to you, but sometimes it gets stuck with old information and a website won't load even though it's actually online.

To flush DNS cache on Windows, press Windows key + R, type cmd, and press Enter. A black command window opens. Type this exactly: ipconfig /flushdns and press Enter. You'll see a message saying "Successfully flushed the DNS Resolver Cache". Close the window. This takes five seconds and fixes most cases where a website is down for you but not for other people.

Clearing cache on a schedule versus as needed

You don't have to clear cache on any particular schedule. Some people do it weekly, some monthly, some only when they notice their computer slowing down. If you use your computer heavily — lots of browser tabs, streaming, downloading — clearing browser cache monthly is reasonable. If you mostly use your computer for email and documents, clearing it every few months is fine.

The one exception is if you're troubleshooting a specific problem: a website showing old information, a program behaving strangely, or your computer running noticeably slower. In those cases, clear cache first before spending time on other fixes. It solves the problem about 30% of the time and takes five minutes.

What cache clearing will and won't do

Clearing cache will speed up your computer if you have gigabytes of temporary files taking up space, or if old cache is causing a website to malfunction. It will not make your computer faster in general if you only have a normal amount of cache. It will not fix viruses, malware, or security problems — that requires different tools. It will not delete your files, documents, photos, or anything you actually care about.

Clearing cache is also not permanent. The moment you visit a website or use a program again, your computer starts building up new cache. This is normal and expected. You're not fighting a losing battle; you're just doing routine maintenance, the same way you might empty a trash can.

Frequently Asked Questions

Will clearing cache delete my passwords or saved credit cards?

No. Passwords and payment information are stored separately from cache. When you clear cache, you're only removing temporary website data. If you want to delete passwords too, you have to check that box separately in the "Clear browsing data" window — and most people should not do that.

What if I clear cache and a website still won't load?

Try flushing DNS cache next (the ipconfig /flushdns command). If that doesn't work, restart your computer and try again. If the website works on someone else's computer or phone, the problem is on your end; if it doesn't work for them either, the website itself is down and you just have to wait.

Can I clear cache automatically without doing it manually?

Yes. In Chrome, go to Settings, click "Privacy and security", then "Clear browsing data". Check "On exit" at the top and select what you want cleared. Firefox has the same option under Settings > Privacy & Security > Cookies and Site Data. This clears cache every time you close the browser.

How much space does cache usually take up?

Browser cache is typically 100 MB to 1 GB depending on how many websites you visit. Windows temporary files can be 500 MB to 5 GB. Neither is usually the reason a computer runs out of space, but clearing both together might free up a few gigabytes if you haven't done it in a year.

Is it safe to delete files in the Temp folder manually?

Yes, as long as you're deleting from the Temp folder (accessed via %temp%) and not from System32 or other Windows system folders. Windows will prevent you from deleting files that are currently in use, so you can't accidentally break anything. If you get an error message, just skip that file and move on.