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Get a cleaner, faster, and smoother-running PC with CCleaner

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Is your PC running slow?

We rely on our computers for work and pleasure so a slow running PC can be incredibly frustrating. If you’ve found yourself asking ‘Why is my pc so slow?”, then we have the answers that can help you get to the bottom of the problem.

One common reason that your PC is slow is that there are too many programs running in the background which are putting pressure on your processor. Sometimes we keep our PC turned on for a long period of time. It’s easier (and lazier) just putting it to sleep overnight rather than turning it off.

Over time this can mean you open a lot of apps that you don’t close down properly. Your computer will continue to run them in the background. This is so that if you want to use the app again, it will load up faster. In this scenario, your PC may perform well for a while until suddenly you realize “my PC is slow”, or maybe even “my PC is very slow”.

Even if you do routinely reboot your PC, you may find that the startup process is sluggish, or your computer’s performance stays sluggish after startup. This is often because many programs have been given permission to run when you start up your computer and will continue to run in the background, eating up resources.

Our PC cleaner software does this by controlling which apps use your computer’s resources so that your computer can run faster. CCleaner also allows for a quicker start-up by letting you disable non-essential programs that are running silently in the background.


  • Why is my PC running slow?

    Fixing a PC that’s running slow requires an understanding of whether there are too many programs running in the background and other common causes. CCleaner’s Performance Optimizer helps you manage these issues and speeds up your PC.

  • Why is my computer suddenly slow?

    A sudden change in your computer’s performance can be due to a number of causes: the overuse of sleep mode, non-essential programs running at startup, and others. CCleaner can speed up your PC, fix common issues, and can save you 34GB of space per year.

  • Why is my PC slow to boot?

    A PC that’s particularly slow when starting up could have multiple programs launching as soon as the operating system starts. CCleaner’s Performance Optimizer detects unnecessary startup items for you and temporarily puts them into ‘Sleep’ mode to free up space.