How to Speed Up a Slow Windows 11 PC: 12 Fixes That Actually Work

By Ammar Aslam · Updated September 10, 2026 · 9 min read

Few things are more frustrating than a computer that takes forever to boot, freezes when you open a browser tab, or makes you wait every time you click a folder. The good news is that most slowdowns on Windows 11 are caused by a handful of common problems, and nearly all of them can be fixed for free in under an hour.

In this guide we walk through twelve fixes, starting with the quickest and safest and moving towards the more involved ones. You do not need to do all of them. Work down the list and check how your PC feels after each step.

1. Find out what is actually slowing you down

Before changing anything, open Task Manager by pressing Ctrl + Shift + Esc. Click the Processes tab and sort by the CPU, Memory and Disk columns. If one column is constantly near 100%, you have found your bottleneck.

High CPU: a program or background process is working too hard.
High Memory: you have too many apps or browser tabs open for your RAM.
High Disk: common on older hard drives, and often the single biggest cause of slowness.

Knowing which one is the problem tells you which of the fixes below will help the most.

2. Disable unnecessary startup apps

Many programs quietly add themselves to startup, so they launch every time Windows boots. Each one adds seconds to your start time and eats memory in the background.

Open Task Manager and select the Startup apps page.
Look at the Startup impact column.
Right-click anything you do not need immediately after logging in, such as game launchers, chat apps or updaters, and choose Disable.

Disabling a startup app does not uninstall it. You can still open it normally whenever you need it.

3. Uninstall programs you no longer use

Go to Settings → Apps → Installed apps and scroll through the list. Trial software, old games, toolbars and duplicate utilities often run background services even when you never open them. Remove anything you do not recognise as necessary. If you are unsure what something is, search its name online before removing it.

4. Free up disk space

Windows needs free space to work with temporary files and updates. When your system drive drops below about 10–15% free space, performance can suffer noticeably.

Open Settings → System → Storage and select Temporary files. Tick the categories you want to remove and click Remove files.
Turn on Storage Sense on the same page so Windows cleans temporary files automatically.
Empty your Downloads folder and Recycle Bin, which quietly grow to several gigabytes over time.

5. Switch to a better power mode

On laptops especially, Windows may limit performance to save battery. Go to Settings → System → Power & battery and set Power mode to Best performance when you are plugged in. The difference can be significant on budget laptops.

6. Reduce visual effects

Animations and transparency look nice but cost resources on older hardware.

Press Windows + R, type sysdm.cpl and press Enter.
Go to Advanced → Performance → Settings.
Choose Adjust for best performance, then re-tick Smooth edges of screen fonts so text still looks sharp.

You can also turn off transparency under Settings → Personalization → Colors.

7. Install Windows and driver updates

Updates frequently include performance and stability fixes. Open Settings → Windows Update, click Check for updates, and install everything available, including anything listed under Advanced options → Optional updates, which is where many driver updates appear. For graphics cards, download the latest driver directly from your card maker's website.

8. Scan for malware

Malware such as cryptocurrency miners and adware can consume huge amounts of CPU. Open Windows Security → Virus & threat protection → Scan options and run a Full scan. It takes a while, but it is thorough. If your PC slowed down suddenly after installing something, this step is especially important.

9. Tame your web browser

For many people, the browser is the real memory hog. Every tab and extension uses RAM.

Remove extensions you do not use.
Enable the browser's memory or efficiency mode, which puts inactive tabs to sleep.
Close tabs you are not actively using, or save them as bookmarks for later.

10. Repair system files

Corrupted system files can cause strange slowdowns and errors. Right-click the Start button, open Terminal (Admin), and run these two commands one after the other:

DISM /Online /Cleanup-Image /RestoreHealth

sfc /scannow

The first repairs the Windows image and the second checks and replaces damaged system files. Restart your PC when both finish.

11. Consider two cheap hardware upgrades

If your PC still has a traditional spinning hard drive (HDD), replacing it with a solid-state drive (SSD) is the single most effective upgrade you can make. Boot times often drop from minutes to seconds, and everyday tasks feel instant.

The second upgrade is RAM. For comfortable everyday use on Windows 11, 8 GB is the practical minimum and 16 GB is ideal if you multitask or keep many browser tabs open.

Upgrade	Best for	Typical impact
HDD → SSD	Slow boot, slow file opening	Very high
More RAM	Slowdowns with many apps/tabs	High

12. Reset Windows as a last resort

If nothing else works, a fresh start often does. Go to Settings → System → Recovery → Reset this PC. Choose Keep my files to keep personal documents while reinstalling Windows and removing apps. Back up your important files first, just in case.

Quick summary: Most slow PCs are fixed by disabling startup apps, freeing disk space, updating Windows and scanning for malware. If your computer still uses a hard drive, an SSD upgrade will make the biggest difference of all.

Frequently asked questions

Do PC cleaner apps help?

Generally, no. Windows already includes everything you need. Many "cleaner" and "booster" apps run in the background themselves and can make things worse.

How often should I restart my PC?

Restarting at least a few times a week clears memory and completes pending updates. Using sleep all the time without restarting can let small problems build up.

Ammar Aslam
Ammar writes clear, practical tech guides that help everyday users fix problems, stay safe online and get more from their devices.