Windows 11 High CPU Usage? How to Fix 100% CPU Problem (2026 Guide)

Is your Windows 11 PC running hot, slow, or constantly lagging? One of the most common reasons is high CPU usage. When CPU usage reaches 90–100%, your system struggles to run even basic tasks.

In this step-by-step guide, you’ll learn how to fix high CPU usage in Windows 11 using safe and proven methods, even if you’re not a technical expert.

What Is High CPU Usage in Windows 11?

CPU usage shows how much processing power your computer is using. When CPU usage stays near 100% for a long time, Windows cannot respond efficiently, leading to freezing, overheating, and poor performance.

• Slow app launches
• System lag and stuttering
• High fan noise
• Overheating

Common Causes of High CPU Usage

1. Background Processes

Some apps and Windows services keep running in the background and consume CPU resources continuously.

2. Too Many Startup Programs

Programs that start automatically with Windows can overload the CPU, especially on older systems.

3. Windows Update Issues

Stuck or looping updates may cause high CPU usage.

4. Malware or Suspicious Software

Malware often uses CPU power without your knowledge.

5. Browser Activity

Heavy browser tabs and extensions can spike CPU usage.

How to Check CPU Usage in Windows 11

1. Press Ctrl + Shift + Esc to open Task Manager
2. Go to the Processes tab
3. Click the CPU column to sort usage

Take note of which processes are consuming the most CPU.

High CPU usage often leads to excessive heat. Learn more about Windows 11 overheating issues and how to fix them to protect your hardware.

Fix #1: Restart Your Computer

A simple restart clears stuck background processes and often reduces CPU usage immediately.

Fix #2: Disable Unnecessary Startup Programs

1. Open Task Manager
2. Go to the Startup tab
3. Disable apps you don’t need at startup

Fix #3: End High-Usage Background Processes

In Task Manager, right-click any app using excessive CPU and choose End task.

⚠️ Avoid ending critical system processes.

Fix #4: Scan for Malware

Malware is a common cause of unexplained CPU spikes.

• Open Windows Security
• Run a Full Scan
• Remove detected threats

Fix #5: Update Windows and Drivers

1. Open Settings → Windows Update
2. Install all available updates
3. Restart your PC

Outdated drivers can cause CPU inefficiencies.

Fix #6: Disable Background Apps

Some apps keep running even when you’re not using them.

1. Open Settings → Apps → Installed apps
2. Select unnecessary apps
3. Disable background permissions

Fix #7: Check Browser CPU Usage

Browsers often cause high CPU usage.

If you use Chrome, excessive memory usage may also contribute to CPU spikes. Learn how to fix Google Chrome high RAM usage for better performance.

Fix #8: Check Disk and Memory Health

CPU issues often appear together with disk or memory problems.

If your PC also experiences storage bottlenecks, read our guide on fixing Windows 11 100% disk usage .

Advanced Tip: Clean Boot Windows 11

A clean boot helps identify problematic third-party software.

1. Press Win + R, type msconfig
2. Go to Services
3. Hide all Microsoft services
4. Disable remaining services

When to Consider Hardware Upgrade

• Old CPU
• Less than 8GB RAM
• Using HDD instead of SSD

Upgrading hardware can dramatically reduce CPU bottlenecks.

Frequently Asked Questions

Is 100% CPU usage dangerous?

Short spikes are normal, but long-term high usage can cause overheating and hardware wear.

Can Windows updates cause high CPU usage?

Yes, especially during installation or if updates get stuck.

Should I disable Windows services?

Only disable non-essential services if you understand their function.

Final Thoughts

High CPU usage in Windows 11 is common but fixable. By managing startup programs, scanning for malware, and optimizing browser behavior, you can restore smooth performance.

Most performance issues are interconnected. Fixing CPU usage often improves memory and disk performance as well.