Understanding Inference Models: What they are and why they matter?


Artificial Intelligence powers everything from chatbots to medical imaging, but there's one concept at the heart of most modern AI applications: inference.
While training large models like GPT or LLaMA gets all the attention, it's inference that actually brings AI to life in apps, assistants, and automations. Whether you’re a developer, researcher, or just curious about how tools like ChatGPT or Ollama work under the hood, understanding inference models is essential.
Let’s break it down.
Inference Model
An inference model is a trained AI or machine learning model that’s being used to make predictions or generate outputs on new data.
You're not teaching the model anymore — you're using what it already knows to do something useful:
- Predict a word, label an image, summarize a document, or generate code.
Example:
Training: Feed a model millions of images of cats and dogs.
Inference: Show it a new image → it tells you “cat”.
In the world of large language models (LLMs), inference means:
Prompt → Model → Text Response
How Inference Happens: The Process
🧾 Input is tokenized (e.g., “Hello” →
[15496]
)⚙️ The model processes the tokens through multiple layers
📤 An output is generated (text, number, label, etc.)
For example, asking an LLM:
“Explain quantum computing in simple terms”
results in a full paragraph written by the model — this is inference.
Inference Platforms vs. Running Models Directly
You can run inference in two main ways:
1. Run Models in Code
Use libraries like PyTorch, Transformers, or TensorFlow:
from transformers import AutoTokenizer, AutoModelForCausalLM
tokenizer = AutoTokenizer.from_pretrained("mistralai/Mistral-7B-Instruct")
model = AutoModelForCausalLM.from_pretrained("mistralai/Mistral-7B-Instruct")
inputs = tokenizer("What is inference?", return_tensors="pt")
outputs = model.generate(**inputs)
print(tokenizer.decode(outputs[0]))
✅ Pros:
Full control
Customisation
Good for research
❌ Cons:
Heavy setup
Requires managing memory, GPUs, dependencies
2. Use Inference Platforms
Platforms like Ollama, Groq, LM Studio, and Hugging Face Inference API provide:
One-command setup
Efficient model execution
REST APIs or CLI tools
Example with Ollama:
# Start LLaMA 3 locally
ollama run llama3
✅ Pros:
Fast and optimised
Low setup effort
Can run locally (Ollama) or in cloud (Groq)
❌ Cons:
Limited customisation
Depends on platform support
Do Inference Models need the Internet?
❌ No, if you're running locally:
Tools like Ollama, LM Studio, or WebUI work completely offline
Great for privacy, edge computing, and offline environments
✅ Yes, if you're using cloud inference:
- Platforms like OpenAI, Anthropic, GroqCloud require an internet connection to access their hosted models
Tool/Platform | Internet Required? | Notes |
Ollama | ❌ No | Local inference engine |
GroqCloud | ✅ Yes | Ultra-fast cloud inference |
Hugging Face API | ✅ Yes | Hosted models |
PyTorch (offline) | ❌ No | After model is downloaded |
Popular Inference Tools
Here are common tools for running inference in different ways:
Tool | Description | Type |
Ollama | Local LLM runner with REST API | Local |
GroqCloud | Fast cloud inference for LLMs | Cloud |
Hugging Face | Model hub + APIs | Cloud/Local |
Text Generation WebUI | GUI for running models locally | Local |
ONNX Runtime | Optimized inference for any backend | Local/Cloud |
vLLM | Fast, scalable server for LLMs | Local/Server |
Final Thoughts
Inference is the final step in the machine learning pipeline — and arguably the most important. It’s where trained models turn theory into action, powering everything from virtual assistants to real-time translation and intelligent automation.
Further Reading
👋 Enjoyed this blog?
Reach out in the comments below or on LinkedIn to let me know what you think of it.
For more updates, do follow me here :)
Subscribe to my newsletter
Read articles from Aakanksha Bhende directly inside your inbox. Subscribe to the newsletter, and don't miss out.
Written by

Aakanksha Bhende
Aakanksha Bhende
Software Engineer | Open Source Enthusiast | Mentor | Learner I love documenting stuff that I come across and find interesting. Hoping that you will love reading it and get to know something new :)