Why Is My Computer So Slow? Seven Fixes to Try Before You Buy a New One

If your computer used to feel quick and now makes you wait for everything, take a breath. In most cases the machine isn't failing. It's simply doing too much at once, or it's running low on room to work. The fixes below go from easiest to most involved, and they work on both Windows PCs and Macs.

What's actually going on when a computer slows down

Think of your computer like a kitchen counter. Memory (called RAM) is the counter space: it holds whatever you're working on right now. Storage is the pantry, where everything is kept long term. When too many programs are open, the counter fills up and the computer starts shuffling things back and forth to the pantry, which is much slower. When the pantry itself is nearly full, even that shuffling gets sluggish. Most slowdowns come down to one of those two problems, plus programs quietly running in the background.

Fix 1: Restart it (really)

This sounds like a joke, but it works. A restart clears the counter and stops programs that have gotten stuck. Many people never actually restart; they just close the lid, so the computer may have been running for weeks. Choose Restart (not Shut Down on Windows, which can keep some settings cached) and see if things improve.

Fix 2: Close what you aren't using, especially browser tabs

Web browsers are among the hungriest programs on any computer. Each open tab takes a slice of memory, and 30 tabs can add up to several gigabytes. Close the tabs you're finished with and bookmark the ones you want later.

Fix 3: See what's hogging your computer

Both systems have a built-in list showing which programs use the most. On Windows, press Ctrl + Shift + Esc to open Task Manager and click the Memory or CPU column heading to sort. On a Mac, open Activity Monitor (search for it with Spotlight, the magnifying glass at the top right) and sort the same way. If one program is using a huge share and you don't need it, close it. Only force-quit things you recognize; if you don't know what something is, leave it alone.

Fix 4: Trim the programs that launch at startup

Many programs add themselves to a list of things that start every time you turn the computer on. Over the years that list grows, and your computer takes longer to become usable. Here's how to prune it:

1. Windows: right-click the taskbar, open Task Manager, and choose the Startup apps tab. Right-click anything you don't need at startup and pick Disable. This doesn't uninstall anything.
2. Mac: open System Settings, choose General, then Login Items. Select an item you don't want and click the minus button.

Fix 5: Free up storage space

A computer needs breathing room to work well. As a rule of thumb, try to keep at least 10 to 15 percent of your storage free. If you're beyond that, delete things you don't need such as old downloads, installers and duplicate photos, and empty the Recycle Bin or Trash. Windows has a Storage settings page and Macs have a Storage page under General in System Settings, and both show what's taking up space.

Fix 6: Install pending updates

Updates often include fixes for bugs that cause slowdowns, and they patch security holes too. If your computer has been nagging you, set aside time to let it finish, then restart. It's worth doing even when your computer isn't slow.

Fix 7: Check for unwanted software

Sometimes a sudden slowdown comes from adware or a browser extension you didn't mean to install. Remove any browser extensions you don't recognize, and uninstall programs you don't remember adding. Windows includes free built-in protection (Windows Security), and running a full scan there is a reasonable step. Be wary of pop-ups claiming your computer is infected and urging you to call a number or buy a cleaner; those are scams, not diagnoses.

Frequently asked questions

Do I need a "PC cleaner" or "speed booster" program?

Almost never. The steps above do what those tools claim to do, for free. Many cleaner programs are themselves a source of pop-ups and extra background load.

Is it just old age?

Sometimes. Computers don't wear out the way tires do, but software keeps getting more demanding. If your machine is many years old, has very little memory (4 GB or less), and still struggles after these fixes, adding memory or switching from a traditional hard drive to a solid-state drive can make an older computer feel new. Ask a trusted shop before buying anything.

When should I get help?

If the computer is loud, very hot, freezing completely, or the slowness started right after you clicked something suspicious, stop and have someone look at it. Back up your photos and documents first if you can.