How well this runs is a question about the model you pick and the machine you pick it for, not about LocalAI itself. The project's own answer on hardware is that requirements "vary based on" the model's size, how much it has been shrunk to fit, and which runner it uses — they publish no minimum, which is honest but unhelpful when you're deciding. Plan for roughly the same ballpark as any other local AI tool: currently around 8 GB of spare memory to run a small model comfortably, and check what your machine has before you start (Task Manager on Windows, About This Mac on a Mac). "No GPU required" is the project's headline claim and it is true — CPU-only is a supported, tested path — but true is not the same as fast.
Which computer you have decides how much work this is. On a Mac there is a proper signed installer you double-click. On Linux there is a plain downloadable program. On Windows there is no installer at all — the project publishes no Windows version, so the route is Docker (a way of running an app in a self-contained box, so you don't install its parts by hand), which is the project's own recommended path on every platform anyway. That is a genuine extra thing to learn. If you're on Windows and you mainly want private AI chat rather than a stand-in for a cloud service, Ollama is a shorter road to the same feeling — come back here when you have something you actually want to point at it.
It is free in the way that matters: MIT-licensed, code public, no account, no card, no usage cap, and — unusually for this category — no paid cloud tier sitting next to it trying to catch you. You will never be asked to pay LocalAI anything. What it does cost you is disk and electricity, and the models are separate downloads of several gigabytes each.
It arrives empty. Installing LocalAI gets you a server and a web page with nothing to talk to; the chat page only lists models you have installed yourself. The project's quickstart names a small, CPU-friendly starter model (currently qwen3-4b) as the first thing to install, which is the sensible place to begin.