How to speed up a slow computer
Most "slow computer" problems come from a short list of causes: too many startup programs, a full disk, pending updates, or a browser drowning in tabs and extensions. Here is the order to fix them.
- Trim startup apps. On Windows, open Task Manager › Startup and disable programs you do not need at boot. On Mac, System Settings › General › Login Items. Fewer startup apps means a faster, lighter machine.
- Free up disk space. A drive that is nearly full slows everything. Empty the Recycle Bin/Trash, remove large files you do not need, and use the built-in cleanup tool (Windows Storage Sense, or About This Mac › Storage).
- Restart and install updates. A pending update or a machine that has not restarted in weeks is a common cause. Restart, then install system updates.
- Tame the browser. Close unused tabs, remove extensions you do not use, and clear the cache. Browsers are the heaviest app on most computers.
- Check for malware. Run a scan with your built-in security tool (Windows Security / macOS protections) if the slowdown is sudden.
If a computer is still slow after all this and it is several years old, the single biggest upgrade is usually moving from a hard drive (HDD) to a solid-state drive (SSD), or adding memory (RAM).
Frequently asked questions
Why is my computer suddenly so slow?
A sudden slowdown is often a pending update, a background program, a nearly full disk, or malware. Restart, free up space, and run a security scan.
Does clearing the cache speed up my PC?
It frees space and can fix a sluggish browser, but it is only one step. Startup apps and free disk space matter more.