Ollama vs LM Studio: Which Local LLM Runner

Short: pick Ollama if you want a scriptable command line and a background API to build on; pick LM Studio if you want a graphical app to browse, download, and chat with models without a terminal. Both run the same GGUF models locally, so this is a workflow choice, not a quality one.

1. Decide by how you work

Ollama is a command-line tool plus a background daemon: you run models in a terminal, and it exposes a local HTTP API for scripts and apps. LM Studio is a desktop application with a model browser, a chat pane, and buttons.

2. Compare install and first run

After install, Ollama is one command:

ollama run llama3.2

Pulls the model if needed and drops you into a chat prompt. LM Studio uses a GUI installer; you then search for a model in the app and click download. See run Ollama on macOS or Linux and get started with LM Studio.

3. Note the shared model format

Both run GGUF models through llama.cpp; LM Studio additionally runs Apple’s MLX models on Apple Silicon. A GGUF you downloaded for one runs in the other, so your quantization choice carries across.

4. Compare the built-in API

Both expose an OpenAI-compatible server, so the same client code talks to either by changing the base URL:

Ollama:     http://localhost:11434/v1
LM Studio:  http://localhost:1234/v1

Point an OpenAI SDK at one of these (1234 is LM Studio’s default in its examples). Ollama’s daemon serves this API whenever it is running; LM Studio serves it once you start its server; see call the Ollama API.

5. Choose for headless and server use

Ollama runs as a service by default, which suits always-on serving on a headless box. LM Studio ships a headless mode too:

lms server start --port 1234

Starts the server from a terminal, no GUI. Both then behave like a local OpenAI endpoint.

If it fails:

OpenAI SDK returns 404: you pointed at the root, not the /v1 base path shown above.
LM Studio server refuses connections: it is not started; toggle the server on or run lms server start.
Ollama API unreachable from another machine: it binds to localhost; set OLLAMA_HOST=0.0.0.0:11434 and restart. Feature details in the LM Studio API docs.