How to Build a Real-Time System Monitor Dashboard Using Python and Flask

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A tutorial published on DEV Community walks developers through creating a lightweight, web-based system monitor dashboard using Python, Flask, and the psutil library. The dashboard tracks CPU, RAM, and disk usage in real time, updating every five seconds via a local Flask server running on localhost. The entire build requires fewer than 100 lines of code and no external cloud services or complex frameworks. Unlike pre-built tools such as htop, a custom dashboard allows developers to set personalized alert thresholds, visualize usage trends, and integrate with their own workflows. The guide also outlines optional extensions, including adding alert notifications when CPU usage exceeds a defined limit.

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