How to Fix High CPU Usage in Windows
High CPU usage can make your Windows PC feel slow, cause apps to freeze, increase fan noise, and reduce gaming performance. In some cases, Task Manager may even show CPU usage close to 100% when you are not doing anything demanding.
The good news is that high CPU usage is often caused by software rather than a failing processor. In this guide, we'll show you how to find what is using your CPU and fix high CPU usage in Windows.
1. Check CPU Usage in Task Manager
Before changing anything, find out which application or process is using your processor.
- Press Ctrl + Shift + Esc to open Task Manager.
- Select the Processes tab.
- Click the CPU column to sort processes by CPU usage.
- Look for applications using an unusually high percentage of the processor.
A temporary CPU spike is normal when opening a program, installing an update, or launching a game. The problem is when CPU usage remains unusually high for an extended period.
2. Close Unnecessary Programs
Running several demanding applications at the same time can quickly increase CPU usage, especially on older or lower-end computers.
Close programs you are not currently using, particularly browsers with many tabs, video editing software, game launchers, and other resource-intensive applications.
If an application is frozen, you can select it in Task Manager and choose End task. Avoid ending Windows processes you do not recognize.
3. Restart Your PC
A restart can fix temporary processes or applications that have become stuck and are consuming excessive CPU resources.
Restart the computer, wait for Windows to finish loading, and check Task Manager again before opening your usual applications.
4. Disable Unnecessary Startup Apps
Some applications automatically launch every time Windows starts. Having too many startup apps can increase background CPU and memory usage.
To review them:
- Open Task Manager.
- Select Startup apps.
- Review the applications in the list.
- Disable programs you recognize and do not need to start automatically.
Do not disable security or system software unless you understand what it does.
5. Update Windows
Keeping Windows updated can resolve bugs and compatibility problems that may contribute to abnormal resource usage.
Open Settings → Windows Update and check for available updates. Install appropriate updates and restart your computer when required.
6. Check for Driver Updates
Hardware drivers allow Windows to communicate with components such as your graphics card, chipset, network adapter, and other devices.
If high CPU usage started after a hardware or software change, check whether an appropriate driver update is available from the device or PC manufacturer.
For graphics hardware, use the official NVIDIA, AMD, or Intel software or support website when checking for GPU drivers.
7. Scan for Unwanted Software
Malicious or unwanted software can sometimes run in the background and consume significant system resources.
Open Windows Security and run a security scan if CPU usage remains unusually high without an obvious explanation.
Be cautious with unknown programs claiming to automatically “boost” your CPU or dramatically speed up Windows.
8. Check Your Browser
Modern web browsers can use considerable CPU resources, particularly when many tabs, videos, web apps, or extensions are running.
If your browser appears near the top of Task Manager, try closing tabs you no longer need and temporarily disabling unnecessary extensions.
Restart the browser afterward and check whether CPU usage improves.
9. Check CPU Temperatures
High temperatures can cause a processor to reduce its operating speed to protect itself. This can make the computer feel slower even when CPU usage is high.
Make sure your computer has adequate airflow and that ventilation openings are not blocked. Excessive dust can also reduce cooling performance.
If your PC becomes very hot or its fans remain unusually loud during light tasks, cooling may be worth investigating.
10. Check CPU Usage While Gaming
High CPU usage during gaming is not automatically a problem. Some games can use a large percentage of the processor, particularly on systems with older CPUs.
However, if the CPU stays near 100% while the game stutters or FPS drops, close unnecessary background programs and reduce CPU-intensive game settings where available.
If you're experiencing poor frame rates, see our guide to fixing low FPS in PC games.
If your computer has limited hardware, you can also read how to run games on a low-end PC.
What CPU Usage Is Normal?
CPU usage constantly changes depending on what your computer is doing. There is no single percentage that is correct for every PC, but the following examples can help you understand what you are seeing.
| Situation | What to Expect |
|---|---|
| Idle or light use | Usually relatively low, with occasional spikes |
| Web browsing | Can vary depending on tabs and websites |
| Gaming | Can be high depending on the game and CPU |
| Rendering or encoding | Very high CPU usage can be normal |
What If CPU Usage Is Still at 100%?
If CPU usage remains close to 100% even after restarting and closing unnecessary applications, return to Task Manager and identify the process responsible.
If several unrelated applications are also crashing, the problem may be broader than CPU usage alone. Our guide on how to fix games that keep crashing on PC covers additional troubleshooting steps for gaming problems.
On an older computer, consistently high CPU usage may also indicate that modern applications are simply demanding more performance than the processor can comfortably provide.
Frequently Asked Questions
Why is my CPU usage at 100%?
A demanding application, background process, Windows task, game, browser, software problem, or unwanted program may be using most of the available CPU resources. Task Manager can help identify the process responsible.
Is 100% CPU usage bad?
Brief periods of 100% CPU usage are not necessarily a problem. For example, demanding workloads may intentionally use all available processor resources. Persistent 100% usage during light tasks deserves further investigation.
Can high CPU usage cause low FPS?
Yes. If a game is limited by CPU performance, heavy CPU usage from the game or background applications can contribute to lower or less stable frame rates.
Does adding more RAM reduce CPU usage?
Not necessarily. RAM and CPU perform different jobs. More memory can help when the system does not have enough RAM, but it will not automatically fix a program that is consuming excessive processor resources.
Final Thoughts
High CPU usage in Windows does not always mean there is something wrong with your processor. Start by using Task Manager to identify the process responsible, then close unnecessary programs, review startup apps, update Windows and drivers, and check for unwanted software.
If CPU usage is mainly high while gaming or performing demanding tasks, it may be normal for your hardware. What matters most is whether the computer remains responsive and performs as expected.