Ever wondered how fast your internet really is? Instead of relying on websites like Speedtest.net, you can write your own Python script to test your connection. With the help of the speedtest-cli library, you can measure download speed, upload speed, and ping directly from the command line.

In this tutorial, we’ll build a Python Internet Speed Test Script step by step, show you how to run it, and even discuss how you can extend it to log results for tracking your internet performance over time.

Requirements

Before starting, make sure you have:

• Python 3.6+ installed

• Internet connection

• A terminal/command prompt

We’ll also install one Python library: speedtest-cli.

Step 1: Install the Required Package

Open your terminal (Command Prompt on Windows, or Terminal on Linux/Mac) and run:

pip install speedtest-cli

This installs the Python library that interacts with Speedtest servers to measure performance.

Step 2: Create the Script

Open your favorite text editor (VS Code, PyCharm, or even Notepad) and create a new file called internet_speed.py.

Paste the following script:

import speedtest

def test_speed():
    st = speedtest.Speedtest()
    st.get_best_server()
    
    print("Testing Download speed...")
    download = st.download() / 1_000_000   # Convert to Mbps
    print("Testing Upload speed...")
    upload = st.upload() / 1_000_000       # Convert to Mbps
    ping = st.results.ping
    
    print("\n--- Internet Speed Test Results ---")
    print(f"Download Speed: {download:.2f} Mbps")
    print(f"Upload Speed  : {upload:.2f} Mbps")
    print(f"Ping          : {ping:.2f} ms")

if __name__ == "__main__":
    test_speed()

Step 3: Run the Script

Navigate to the folder where you saved the file and run:

python internet_speed.py

You’ll see output like this:

--- Internet Speed Test Results ---
Download Speed: 52.34 Mbps
Upload Speed  : 11.45 Mbps
Ping          : 23.67 ms

Understanding the Results

• Download Speed (Mbps): How fast you can receive data (important for streaming, browsing, downloads).

• Upload Speed (Mbps): How fast you can send data (important for video calls, uploads, cloud backups).

• Ping (ms): The delay between your computer and the server (lower is better for gaming and calls).

Bonus: Extend the Script

You can extend this script to:

• Log results into a CSV file for historical tracking.

• Schedule it with Task Scheduler (Windows) or cron (Linux/Mac) to run automatically at set times.

• Send alerts if your speed drops below a certain threshold.

For example, to save results in a CSV:

import speedtest, csv, datetime

def log_speed():
    st = speedtest.Speedtest()
    st.get_best_server()
    download = st.download() / 1_000_000
    upload = st.upload() / 1_000_000
    ping = st.results.ping
    time_now = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")

    with open("speed_log.csv", "a", newline="") as file:
        writer = csv.writer(file)
        writer.writerow([time_now, f"{download:.2f}", f"{upload:.2f}", f"{ping:.2f}"])
    
    print("Result logged at", time_now)

if __name__ == "__main__":
    log_speed()

Conclusion

With just a few lines of Python, you’ve created a powerful internet speed test tool that measures download, upload, and ping directly from your terminal. Unlike online speed test websites, this script is fully customizable — you can log results, schedule tests, or even integrate it into monitoring dashboards.

If you’re learning Python, this is a fun and practical project to improve your coding and networking skills while keeping an eye on your internet provider’s performance.