Start with the basics: dust and debris removal

The fastest way to improve your computer's performance is to remove dust from the fans and vents. Dust blocks airflow, which makes your machine run hotter and slower. You can do this without opening your computer at all.

Power off your computer completely and unplug it. Wait five minutes. Use a can of compressed air held upright, and spray short bursts into the vents on the sides, back, and bottom of your machine. Hold the can about three inches away. If you have a desktop, you can also open the side panel (usually held by two thumbscrews) and spray the internal fans directly — the CPU fan, GPU fan if you have one, and the case fans. Let any dust settle for a minute, then spray again. Do not touch the fans while they spin; let them stop on their own.

For a laptop, spray the vents along the sides and back. Laptops are harder to open safely, so external cleaning is usually enough. If your laptop is several years old and still runs hot, a repair shop can disassemble it and clean the internal heatsink for $50 to $100.

Key Takeaways

  • Dust buildup in fans and vents is the most common reason computers slow down and overheat; compressed air removes it without opening your machine.
  • Deleting old files, uninstalling unused programs, and clearing your browser cache frees up storage space and can speed up startup time.
  • Running Disk Cleanup on Windows or emptying the Trash and using Storage Management on Mac removes temporary files your system no longer needs.
  • Malware and viruses slow your computer down; Windows Defender (built into Windows) and Malwarebytes scan for and remove them at no cost.
  • A full restart clears your RAM and closes background programs, which often solves slowness without any other work.

Clear out files and programs you no longer use

Files and programs take up storage space. When your drive gets full, your computer has to work harder to find and load data, which slows everything down. Removing what you do not need is one of the fastest fixes.

On Windows, open Settings, go to System, then Storage. You will see a breakdown of what is using space: apps, documents, downloads, temporary files, and more. Click on each category to see what is inside. Delete old downloads you no longer need — most people have gigabytes of installers and files they downloaded months ago. Go to your Documents and Downloads folders and sort by date modified; anything older than a year is probably safe to delete. Right-click and select Delete, then empty the Recycle Bin.

On Mac, click the Apple menu, go to About This Mac, then Storage. You will see a similar breakdown. Click Manage to see recommendations. Delete old files from Downloads and Documents the same way — sort by date, select what you do not need, and drag it to the Trash. Empty the Trash from the Dock.

Next, uninstall programs you do not use. On Windows, go to Settings, Apps, Apps & Features. Scroll through the list and click on anything you recognize but do not use, then Uninstall. On Mac, open Applications in Finder, select an app you do not use, and drag it to the Trash. Some programs leave behind settings files; if you want to remove them completely, use a free tool like AppCleaner, which finds and deletes those leftover files.

Run your system's built-in cleanup tools

Both Windows and Mac have tools that remove temporary files your system creates while running. These files pile up over time and waste space.

On Windows 10 or 11, open Settings, go to System, then Storage. Click Temporary Files. Check the boxes next to Temporary Files, Recycle Bin, and Downloads (if you want). Click Remove Files. Windows will delete them when ready. You can also run Disk Cleanup the old way: press Windows Key + R, type cleanmgr, and press Enter. Select your C: drive, click OK, check the boxes for Temporary Internet Files, Temporary Files, and Recycle Bin, then click Delete Files.

On Mac, there is no single built-in cleanup tool like Windows has. Instead, go to Apple menu, About This Mac, Storage, then Manage. Click Empty Trash Automatically and set it to delete items after 30 days. You can also use the free tool Disk Diag or CleanMyMac X (paid, but has a free trial) to find and remove old cache files, but the manual method of deleting old files from Downloads and Documents usually solves the problem.

Scan for malware and viruses

Malware and viruses run in the background and consume your computer's resources, making it slow and unresponsive. They can also steal your data. Scanning for them is free and takes 20 to 60 minutes depending on how much data you have.

On Windows, Windows Defender is built in and runs automatically in the background. To run a full scan manually, open Windows Security (search for it in the Start menu), click Virus & Threat Protection, then Scan Options. Select Full Scan and click Scan Now. Your computer will scan every file on your drive. This can take an hour or more, so run it when you do not need to use your machine.

On Mac, built-in protections are less visible, but Malwarebytes is free and widely trusted. read it from malwarebytes.com, install it, open the app, and click Scan. It will check your system for known malware. If it finds anything, it will show you what it is and ask whether to remove it.

If a scan finds malware, let the tool remove it. If Windows Defender or Malwarebytes cannot remove something, restart your computer in Safe Mode (Windows: restart, hold Shift, select Troubleshoot, then Startup Settings, then Safe Mode; Mac: restart and hold Command + S) and run the scan again. Safe Mode loads only essential programs, which gives the security tool a better chance to remove stubborn infections.

Clean your keyboard, screen, and ports

Physical dirt on your computer can cause problems. Dust in ports can prevent cables from connecting properly. Grime on your screen makes it harder to see. Debris under keys can cause them to stick.

For your keyboard, power off your computer first. Turn the keyboard upside down and tap it gently over a trash can to dislodge crumbs and dust. Use a can of compressed air to blow out debris between the keys. If keys are sticky, dip a cotton swab in rubbing alcohol (70 percent isopropyl), squeeze out the excess, and clean around the key. Do not pour liquid on the keyboard.

For your screen, power off and unplug. Use a microfiber cloth (the kind that comes with glasses) slightly dampened with distilled water. Wipe gently in circular motions. Do not use paper towels, tissues, or tap water — they can scratch the screen or leave mineral deposits. For stubborn smudges, use a screen cleaning solution made for electronics, not window cleaner.

For ports (USB, charging, headphone jack), use a dry cotton swab or a small brush to remove dust. If a port is corroded or has visible damage, do not force a cable into it — take your computer to a repair shop.

Restart your computer regularly

A restart clears your computer's RAM (temporary memory) and closes all background programs. Many slowness problems disappear after a restart because your system is no longer juggling dozens of open processes.

Restart at least once a week, or more often if you notice slowness. On Windows, click the Start menu, click the Power button, and select Restart. On Mac, click the Apple menu, select Restart, and confirm. Let your computer fully shut down and boot back up — this usually takes two to five minutes. Do not just put it to sleep; sleep mode does not clear RAM or close background programs the way a restart does.

If your computer is very slow, restart it before trying anything else. You may find that is all you needed to do.

Check your browser and clear cached data

Your web browser stores copies of web pages, images, and login information to load websites faster next time. Over months and years, this cache grows to gigabytes and can slow your browser down. Clearing it is safe and takes two minutes.

In Chrome, click the three-dot menu in the top right, go to Settings, click Privacy and Security, then Clear Browsing Data. Select All Time, check Cookies and Other Site Data and Cached Images and Files, and click Clear Data. In Firefox, click the menu button (three horizontal lines), go to Settings, click Privacy & Security, scroll to Cookies and Site Data, and click Clear Data. In Safari, click Safari in the menu bar, go to Preferences, click Privacy, then Manage Website Data, select all, and click Remove.

You can also set your browser to clear this data automatically when you close it. In Chrome, go to Settings, Privacy and Security, and toggle on Delete Cookies and Site Data When You Quit Chrome. In Firefox, go to Settings, Privacy & Security, scroll to Cookies and Site Data, and check Delete Cookies and Site Data When Firefox Is Closed. In Safari, go to Preferences, Privacy, and check Remove All Website Data When Quitting Safari.

Update your operating system and drivers

Updates patch security holes, fix bugs that cause slowness, and improve performance. Delaying updates leaves your computer vulnerable and can make it run slower.

On Windows, open Settings, go to Update & Security (or System, then Windows Update on Windows 11), and click Check for Updates. Windows will read and install any available updates. You may need to restart. Set Windows to install updates automatically: in the same menu, click Advanced Options and toggle on Receive Updates for Other Microsoft Products.

On Mac, click the Apple menu, go to System Settings (or System Preferences on older versions), click General, then Software Update. If updates are available, click Update Now. Mac usually installs updates automatically, but you can check this setting in the same menu.

For drivers (software that lets Windows talk to your hardware), Windows Update usually handles this automatically. If you have a graphics card, printer, or other device that is not working well, visit the manufacturer's website, find the Support or Downloads section, and read the latest driver for your exact model. Run the installer and restart.

Frequently Asked Questions

How often should I clean my computer?

Clean the outside (keyboard, screen, vents) every month. Run internal cleaning (deleting files, scanning for malware, clearing cache) every three months. If your computer is in a dusty environment or you use it heavily, clean it more often. A restart once a week prevents most slowness problems.

Is it safe to open my desktop computer and clean the inside?

Yes, if you follow basic precautions. Power off completely, unplug the machine, wait five minutes, and touch a metal part of the case to discharge static electricity before touching components. Use compressed air only — do not use a vacuum, which can create static. If you are not comfortable doing this, a repair shop can clean it for $30 to $75.

Will cleaning my computer make it faster?

Yes, but only if slowness is caused by dust, full storage, or background programs. If your computer is old or has a slow hard drive, cleaning will help but may not make it feel new. A restart and malware scan solve most slowness problems quickly.

What should I do if my computer still runs slowly after cleaning?

Check how much free storage you have left (if less than 10 percent, delete more files). Open Task Manager on Windows (Ctrl + Shift + Esc) or Activity Monitor on Mac (Applications, Utilities) and look for programs using a lot of CPU or memory — close ones you do not need. If nothing helps, your hard drive may be failing or your RAM may be full; a repair shop can diagnose this for $50 to $100.

Can I damage my computer by cleaning it?

Physical cleaning is safe if you power off and unplug first. Avoid touching circuit boards or components directly. Compressed air is safe; vacuums and liquids are not. Deleting files is safe as long as you do not delete system files (Windows, Program Files, System32 on Windows; Library, System on Mac). Stick to Downloads, Documents, and Trash, and you will not cause problems.