How to Set Up GPT API on a Raspberry Pi
Running AI on a tiny computer sounds futuristic, but with the Raspberry Pi and the OpenAI GPT API, it’s easier than ever. In this guide, we’ll cover step by step how to set up GPT API on a Raspberry Pi, plus the exact supplies you need to get started.
Supplies You’ll Need
Here’s everything required to follow this tutorial. These links include my Amazon affiliate tag rasmurtech-20:
- Raspberry Pi 5 (8GB Recommended)
👉 Buy on Amazon - Official Raspberry Pi Power Supply
👉 Buy on Amazon - MicroSD Card (128GB SanDisk Recommended)
👉 Buy on Amazon - Raspberry Pi Case with Cooling Fan
👉 Buy on Amazon - USB Keyboard and Mouse (for setup if not going headless)
👉 Buy on Amazon - HDMI Cable for Setup
👉 Buy on Amazon - Ethernet Cable (optional if not using Wi-Fi)
👉 Buy on Amazon
Step 1: Update Your Raspberry Pi

Open the terminal and run:
sudo apt update && sudo apt upgrade -y
Step 2: Install Python and Pip
Check if Python is installed:
python3 --version
If missing, install it with:
sudo apt install python3 python3-pip -y
Step 3: Create a Virtual Environment
This step keeps your GPT project dependencies clean:
sudo apt install python3-venv -y
python3 -m venv gpt_env
source gpt_env/bin/activate
Step 4: Install the OpenAI Library
Inside the environment, install:
pip install openai
Step 5: Get and Save Your API Key
- Go to OpenAI API Keys.
- Generate and copy your key.
Save it as an environment variable:
echo "export OPENAI_API_KEY='your_api_key_here'" >> ~/.bashrc
source ~/.bashrc
Step 6: Write a Test Script

Create gpt_test.py:
nano gpt_test.py
Paste this code:
import os
from openai import OpenAI
client = OpenAI(api_key=os.getenv("OPENAI_API_KEY"))
response = client.chat.completions.create(
model="gpt-4o-mini",
messages=[
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hello, Raspberry Pi world!"}
]
)
print(response.choices[0].message.content)
Save and exit (CTRL+O, Enter, CTRL+X).
Step 7: Run the Script

python3 gpt_test.py
You should see GPT reply directly in your terminal 🎉.
Expand Your Project
Once you know how to set up GPT API on a Raspberry Pi, you can build:
- A voice assistant (using a USB mic and speaker).
- An IoT controller (link GPT to smart devices).
- A web-based chatbot (with Flask or FastAPI).
- A debugging helper for your Raspberry Pi coding projects.
Troubleshooting
- No module named openai → Activate your virtual environment.
- API key not found → Run
echo $OPENAI_API_KEYto verify. - Slow responses → Use lighter models like
gpt-4o-mini.
Conclusion
By following this guide, you’ve learned how to set up GPT API on a Raspberry Pi. With just a few commands, you can now bring AI-powered projects to life on one of the smallest, most versatile computers available.
How to Set Up GPT API on a Raspberry Pi – FAQ
Q1: Do I need a Raspberry Pi 5, or will a Pi 4 work?
A: Both work. A Pi 4 (2GB+) is fine for API calls, while a Pi 5 is snappier for multitasking or running web apps alongside the API.
Q2: Which Python package should I install?
A: Use the official openai Python SDK. Install it inside a virtual environment with pip install openai.
Q3: Where do I put my OpenAI API key?
A: Store it as an environment variable for safety:echo "export OPENAI_API_KEY='YOUR_KEY'" >> ~/.bashrc && source ~/.bashrc
Q4: I get “ModuleNotFoundError: openai.” What’s wrong?
A: You likely didn’t activate your venv. Run source gpt_env/bin/activate, then reinstall with pip install openai.
Q5: Which model should I call from the Pi?
A: For speed and low cost, start with a lightweight model such as gpt-4o-mini. You can change models later if you need more capability.
Q6: Can I run the model locally on the Pi?
A: This guide uses the cloud API (recommended). Full LLMs are heavy; local models on a Pi are possible but much slower and more complex to set up.
Q7: How much will this cost?
A: Costs depend on tokens used. Keep prompts short, cache system messages, and log usage while testing.
Q8: How do I secure my API key on a shared Pi?
A: Don’t hard-code keys. Use environment variables, .env files with strict permissions, or systemd service files that inject the key at runtime.
Q9: Can I build a voice assistant with this setup?
A: Yes. Add speech-to-text (e.g., Vosk or Whisper API) and text-to-speech (e.g., pyttsx3 or an online TTS) around the same GPT call.
Q10: My requests are slow—any tips?
A: Use a faster model, reduce prompt size, avoid large response tokens, and keep your Pi wired via Ethernet for better latency.
