How to Speed Up a Slow Computer — 10 Fixes That Actually Work
Before you buy a new computer or install “speed booster” software, try these fixes. Most take under 10 minutes and cost nothing.
1. Restart Your Computer
The simplest fix. Restarting clears temporary memory, stops background processes, and applies pending updates.
If your computer hasn’t been restarted in weeks, this alone can restore performance.
2. Find What’s Using Your CPU
Open Task Manager (Windows) or Activity Monitor (macOS) and sort by CPU usage.
Windows: Ctrl+Shift+Esc → Processes tab → Click “CPU” column header
macOS: Applications → Utilities → Activity Monitor → Sort by “% CPU”
If a single application is using 90%+ and you don’t need it, close it.
3. Close Browser Tabs
Each open tab uses memory. If you have 20+ tabs open:
- Use browser bookmarks instead of keeping tabs open for later
- Install OneTab (Firefox/Chrome) to collapse all tabs into a single list
- Restart the browser after closing tabs
4. Free Up Disk Space
Most operating systems slow down when the disk is over 90% full.
| OS | What to do |
|---|---|
| Windows | Settings → System → Storage → Turn on Storage Sense |
| macOS | Apple menu → System Settings → General → Storage |
| Linux | sudo apt autoremove && sudo apt autoclean |
Aim for at least 20% free space on your system drive.
5. Check for Background Updates
Operating system updates can run silently in the background, consuming CPU and disk. Check if updates are currently installing and schedule them for off-hours.
6. Disable Startup Programs
Many programs configure themselves to start automatically. Most don’t need to.
Windows: Ctrl+Shift+Esc → Startup tab → Disable everything you don’t need daily
macOS: System Settings → General → Login Items
Linux: No equivalent — you’d need to check your desktop environment settings.
7. Scan for Malware
If your computer is suddenly slow, it could be malware.
- Windows: Run Windows Defender (built-in, free, good enough)
- macOS/Linux: Less common but not impossible. Run Malwarebytes or ClamAV.
8. Add More RAM (Best Performance Upgrade)
If your computer has only 4-8GB of RAM and you regularly use many applications, upgrading to 16GB is the single most impactful hardware change. RAM is relatively cheap and easy to install on most desktop computers and some laptops.
9. Switch to an SSD
If your computer still uses a mechanical hard drive (HDD), switching to a Solid State Drive (SSD) is the next best upgrade. A modern SSD makes your computer feel brand new — boot times drop from minutes to seconds.
10. Do a Clean OS Install (Last Resort)
If nothing works, back up your files and reinstall the operating system from scratch. This removes years of accumulated junk software, failed driver attempts, and configuration drift.
Windows: Settings → System → Recovery → Reset this PC
macOS: Restart + hold Cmd+R → Disk Utility → Reinstall macOS
Linux: Most distros offer a “reinstall” option from the live USB
Need more help? Try our git and command guides if you’re working on a Linux or developer machine.