Introduction
If your computer has been running slowly lately, you’re not alone. This is one of the most common problems people face at home, and it happens to both Windows PCs and Macs.
The good news is that in most cases, you don’t need to buy a new computer. You don’t need to call anyone, and you certainly don’t need to spend hundreds of pounds or dollars.
This guide draws on the same three steps I’ve walked countless customers through over the years — it explains why computers slow down and shows you three simple solutions you can try yourself, at no cost, with no technical experience needed.
Why Does a Computer Slow Down?
Before jumping into the solutions, it helps to understand what causes the problem. Here are the most common reasons:
- The computer hasn’t been restarted in a long time
- Windows or macOS updates are waiting to be installed
- Temporary files and old data have built up over months or years
- Too many browser tabs or programmes are open at once
- Too many programmes start up automatically when you turn the computer on
- Unwanted software or malware is running quietly in the background
- The hard drive is nearly full, or the computer doesn’t have enough memory (RAM)
- A slow internet connection is making websites and apps feel sluggish
The three solutions below address every one of these causes.
Solution 1: Restart Your Computer Properly
This sounds almost too simple — but it genuinely resolves a huge number of slow computer problems, and most people have never actually done it correctly.
There’s an important difference between closing a laptop lid and actually restarting the computer. Closing the lid just puts it to sleep. It doesn’t clear the programmes running in the background. Over days and weeks, these programmes pile up and slow everything down.
A proper restart closes everything and gives your computer a clean start.
How to restart on Windows:
- Click the Start button (the Windows logo in the bottom-left corner of your screen)
- Click the Power icon
- Choose Restart — not Shut Down and not Sleep
- Wait for the computer to fully close and start up again
- Give it a couple of minutes before opening anything
How to restart on a Mac:
- Click the Apple icon in the top-left corner
- Choose Restart
- If a tick box appears asking to “Reopen windows when logging back in,” untick it
- Wait for it to fully restart before opening anything
How often should you restart?
At least every three or four days. If you use your computer every day, a quick restart each evening is a good habit. After a proper restart, many people notice things feel faster straight away.
If your computer is still slow after restarting, move on to Solution 2.
Solution 2: Stop Programmes From Starting Automatically
Every time you install something new — a PDF reader, a printer tool, a music app — it often adds itself to your computer’s startup list. This means it starts running quietly in the background every single time you turn on your computer, even if you never actually use it.
Over time, five or ten of these programmes can be running at once before you’ve even opened anything. That uses up memory and slows everything down.
The solution is simple: turn off the ones you don’t need.
How to do this on Windows 10 or Windows 11:
- Press Ctrl + Shift + Esc on your keyboard at the same time — this opens Task Manager. Or press the Windows key and type “Task Manager” in the search box, then click it.
- Click the Startup tab along the top
- You’ll see a list of programmes. Look at the Status column — anything that says “Enabled” starts automatically
- Right-click on any programme you don’t use regularly and choose Disable
- Repeat for any others you don’t recognise or rarely use
- Restart your computer when you’re done
How to do this on a Mac:
- Click the Apple icon, then System Settings (or System Preferences on older Macs)
- Go to General, then Login Items
- You’ll see a list of apps that open automatically at login
- Select any you don’t need and click the minus (–) button to remove them
After doing this and restarting, most people notice their computer starts up noticeably faster.
Solution 3: Free Up Storage Space on Your Hard Drive
Your computer needs free space on its hard drive to work properly. When it gets too full, even basic tasks become a struggle.
A good rule of thumb: always keep at least 10 to 15 per cent of your hard drive free. For a 500GB drive, that means keeping at least 50 to 75GB clear.
How to check how much space you have on Windows:
- Open File Explorer (the folder icon on your taskbar)
- Click This PC on the left
- You’ll see your hard drive with a bar showing how much space is used and how much is free
How to check on a Mac:
- Click the Apple icon, then About This Mac
- Click Storage to see a colourful breakdown of what’s using your space
What to delete to free up space:
- Downloads folder — Most people have hundreds of old downloaded files they’ve completely forgotten about. Open your Downloads folder and delete anything you no longer need.
- Recycle Bin — Files you delete go here first. Right-click the Recycle Bin on your desktop and choose “Empty Recycle Bin” to actually remove them.
- Old photos and videos — These take up the most space. Consider moving them to an external hard drive or a free service like Google Photos or iCloud.
- Temporary files on Windows — Press the Windows key + R, type temp, press Enter, then select all files and delete them. Repeat with %temp%.
Use Windows built-in Storage Sense:
- Go to Settings, then System, then Storage
- Turn on Storage Sense — Windows will then clean up temporary files automatically on a regular basis
After freeing up space and restarting, your computer should feel noticeably more responsive.
Still Slow? Check for Updates
If you’ve worked through all three solutions and things are still sluggish, it’s worth checking for system updates.
Microsoft and Apple release updates regularly that resolve bugs and improve performance. If your computer hasn’t been updated in a while, this alone can cause ongoing slowness.
How to check on Windows:
- Go to Settings, then Windows Update
- Click Check for Updates
- If any are available, install them and restart when prompted
How to check on a Mac:
- Go to Apple icon, then System Settings, then General, then Software Update
When Might It Be Time for a New Computer?
These solutions resolve the vast majority of slow computer problems I come across. That said, if your computer is more than eight to ten years old, the hardware itself may simply be too old to run modern software well.
Signs that the hardware might be the issue:
- The computer is slow even right after a fresh restart
- It struggles to open basic things like a web browser or a Word document
- It takes more than five minutes to start up even after trying everything above
- You’re seeing a black screen, frequent freezing, or it stops responding altogether
In this case, it’s worth visiting a local, trusted computer shop for an honest opinion. A good shop will tell you whether something like adding more memory could help, or whether a replacement makes more sense. Always ask for a written quote, and get a second opinion before spending money.
To Sum It Up
A slow computer is frustrating — but it’s almost never a disaster. Before you worry, before you call anyone, and before you spend a single penny, try these three solutions first:
- Restart your computer properly
- Stop unnecessary programmes from starting up automatically
- Free up space on your hard drive
Thousands of people have used steps exactly like these to bring a sluggish computer back to life — without spending anything at all.
If this guide helped you, please share it with a friend or family member who’s having the same problem. You’ll find more free guides on OnlineSafeGuide.com covering printer help, internet safety, and everyday computer advice.
This website is a free, independent educational resource. We are not affiliated with Microsoft, Apple, or any other company mentioned in this guide. Always check official sources for the most up-to-date guidance.
Frequently Asked Questions
My computer was fine last week but has suddenly become very slow. What happened?
A sudden slowdown is usually caused by a Windows or macOS update running in the background, a recently installed programme, or the hard drive becoming very full. Try a proper restart first — it resolves this more often than you might expect.
How do I know if unwanted software is making my computer slow?
Download and run a free scan using Malwarebytes. The free version is very effective at finding and removing unwanted programmes. You don’t need the paid version for a basic scan.
Will adding more memory (RAM) make my computer faster?
It can help, particularly if your computer struggles when you have several things open at once. That said, try the three solutions in this guide first — they’re free and often solve the problem without any hardware changes needed.
Is it safe to delete files from the Temp folder?
Yes, completely safe. Temporary files in the Temp folder are leftovers from programmes and updates. Deleting them frees up space and causes no harm. Your computer will create new temporary files as needed