Same question, two routes, below. One leaves your computer. One never does.

On the left, a model behind an [API](/what-is-an-api-2026) on the provider's servers. On the right, a local model running on your own machine.

API vs local, side by side

Who sees your prompts

API (provider's servers)
The provider, under their terms
Local (your machine)
No one else, when run locally

How you pay

API (provider's servers)
Per token, every request
Local (your machine)
Hardware up front, electricity after

Which models

API (provider's servers)
Closed models (e.g. Claude, OpenAI's GPT)
Local (your machine)
Open-weight models (e.g. gpt-oss, Qwen)

What limits you

API (provider's servers)
Rate limits and budget
Local (your machine)
Your GPU's memory (VRAM)

Privacy is the big one. Ollama's FAQ: "Ollama runs locally. We don't see your prompts or data when you run locally."

The limit is memory. A model has to fit in your graphics card's VRAM to run well. Our VRAM calculator shows what fits your card.

Cost flips. An API costs per request; local costs up front. Cost to run compares the two for real models, and cloud GPU prices sit in between.

It's the same idea underneath: tokens, a context window, sampling. Only where it runs changes.

Try it with the rules off. In the sandbox, send a prompt containing a fake customer email both ways, then check where it went. Then pick a model too big for your card and see what happens.

Check yourself

0/4 got it

Saved on this device only. No account, no streaks.