LLM types by Access Levels
1. First introduction
LLMs can be closed, open-weights or open-source types.
Closed models are rented, open-weights models are downloadable, and open-source models are fully transparent and modifiable.
- Closed models are rented. You can only access them through paid APIs or apps, and you never see or control the actual model.
- You cannot download closed models. The model weights and training process remain secret, so you fully depend on the provider’s servers and policies.
- Open-weights models are downloadable. You can run them on your own machines or servers, but you may not get full training code or data details.
- Open-weights give technical freedom, not full transparency. You can fine-tune and deploy them, but the original training pipeline is partly hidden.
- Open-source models are fully transparent and modifiable. You can inspect, modify, retrain, and deploy the entire stack, making them best for research, sovereignty, and deep customization.
2. Going deeper
“Open vs Closed” is about ownership and control. Access mode is about how you use a model, not how open it is.
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API-only models (cloud-rented access)
You don’t run the model yourself. Your app sends requests to a company’s servers, and you get responses. This is easy to use but creates dependency on pricing, policies, outages, and geopolitical controls. -
Self-hostable models (run on your own servers)
You download the model and deploy it on your own machines or cloud accounts. This gives more control over data privacy, latency, and costs, but you must manage hardware, scaling, and security yourself. -
Edge models (run on phones and devices)
These models are optimized to run locally on devices like smartphones, laptops, cars, and IoT hardware. They reduce cloud dependency, improve privacy, and work offline, but are smaller and less capable than large cloud models. -
Distilled models (smaller copies of big models)
Distilled models are trained to mimic larger, more powerful models while using fewer parameters and less compute. They are cheaper, faster, and easier to deploy, but usually less accurate and less capable on complex tasks.
Openness decides who controls the model; access mode decides where and how the model runs.
Let's take a look at these four types below.