How Do I Check My CPU Usage On Raspberry Pi?

To check CPU usage on a Raspberry Pi, the fastest way is to open a terminal and run the top command, it gives you a live, text-based breakdown of every running process and the total CPU percentage at the top of the screen. If you want a more visual and interactive view, htop is a better choice, and for a graphical option, the pre-installed System Monitor app shows a real-time CPU graph without touching the command line.

How to check CPU usage raspberry pi instantly with the top command

The top command is included in every Raspberry Pi OS installation, so there's nothing to install. It refreshes every few seconds and shows a real-time, text-based view of CPU usage per process and system load averages. This is the quickest way to see which program is hogging your processor, especially when your Pi feels sluggish.

1. Open a terminal window.
2. Type top and press Enter.
3. Look at the top few lines for the overall CPU percentage (the %Cpu(s) row).
4. Scroll through the process list to find the highest CPU consumers.
5. Press q to exit.

The load average appears in the top line, showing the system load over 1, 5, and 15 minutes. If those numbers are consistently higher than the number of CPU cores (typically 4 on a Raspberry Pi 4 or 5), your Pi is under heavy load. The top output also shows memory usage and uptime, making it a solid first stop for any performance question.

Using htop for a more visual CPU monitor

If you find top too cramped or hard to read, htop is a popular upgrade. It's an interactive process viewer that offers improvements over top with a more user-friendly interface, including color-coded CPU bars and a scrollable process list. You can install it with a single command, and once running, it updates live so you can watch CPU usage change as you launch or close programs.

1. Install it: sudo apt install htop.
2. Launch it by typing htop in the terminal.
3. At the top, you'll see a row of CPU bars, one per core. Green indicates normal user processes, red indicates kernel (system) activity, and blue indicates low-priority (nice) processes.
4. Press F6 to change the sort column and choose, for example, CPU% to list the heaviest processes first.
5. Press Shift+H to disable thread view and see only processes, which reduces clutter.
6. Exit with q or F10.

htop displays a complete list of running processes and their resource consumption, so you can spot a runaway program instantly. The color coding makes it easy to tell at a glance whether the load comes from your own apps (green), system tasks (red), or background low-priority jobs (blue). It's the go-to tool for anyone who spends time in the terminal.

Checking CPU usage with the Raspberry Pi system monitor app

If you prefer a graphical interface, the Raspberry Pi OS includes a System Monitor application that shows CPU usage as a live graph. It's pre-installed, so you don't need to install anything, and it's perfect for users who want a visual representation without memorizing commands.

1. Click the Raspberry Pi menu icon in the top-left corner of the desktop.
2. Navigate to System Tools and select System Monitor.
3. Click the Resources tab.
4. You'll see a graph of CPU usage history, updating in real time.
5. Below the graph, you'll find the current CPU percentage and per-core breakdown.

The System Monitor also shows memory and network activity on the same screen, giving you a broader view of your Pi's health. It's the easiest method for beginners, and it's particularly useful when you want to watch CPU usage over a few minutes to see if a pattern emerges, like a spike during a specific task.

Alternative: all-in-one monitoring with Glances

For a terminal-based tool that goes beyond just CPU, Glances is an all-in-one performance monitoring tool that can be run from the terminal by typing glances, providing CPU temperature, disk I/O, and network traffic in addition to CPU usage. This makes it a great choice when you need to diagnose a performance problem that might involve multiple subsystems, for instance, if your Pi is slow because the SD card is thrashing, not because the CPU is maxed out.

1. Install it: sudo apt install glances.
2. Run it by typing glances in the terminal.
3. You'll see a dashboard with CPU usage, memory, disk I/O, network speed, and CPU temperature all at once.
4. Use the arrow keys to navigate between sections, and press q to exit.

Glances is especially handy when you want to check the health of your Raspberry Pi SD card, because it shows disk I/O and read/write speeds right next to CPU usage. That way, you can see whether a slow process is caused by processor load or by storage bottlenecks. It's a single dashboard that answers most performance questions without needing multiple commands.

Understanding your Raspberry Pi CPU load

The uptime command gives you a quick snapshot of system load without any installation. Run it in the terminal, and you'll see something like load average: 0.50, 0.40, 0.35. These three numbers represent the average number of processes waiting for CPU time over the past 1, 5, and 15 minutes. If the 1-minute average is much higher than the 15-minute average, your Pi has just experienced a spike in activity, perhaps a background update or a heavy script started running.

For single-board computers, load averages can be misleading if you don't account for the number of cores. Always compare the load to your specific model's core count. High load averages combined with high CPU usage in top or htop confirm that your processor is the bottleneck. If the load is high but CPU usage is low, the problem might be disk I/O or memory swapping, which is where tools like Glances or the System Monitor's memory graph become useful. If you're also worried about overheating, you can use vcgencmd measure_temp to check CPU temperature, though that's a separate metric from usage; for a graphical alternative on Windows, you can check CPU temp in task manager. Knowing your load average helps you decide whether to close programs, reduce background services, or upgrade to a faster Pi model.