# Connect Models

> Connecting an AI service is what puts models in Big-AGI: where to start, one key for many models, every service in the app, the model each job uses, and models on your own machines.

- Canonical: https://big-agi.com/docs/connect-models
- Minimum tier: open  [Open ⊂ Free ⊂ Pro - a tier only ever ADDS to the Open baseline]
- Kind: decision · Last content update generation: 2026-07-27 · Review by: 2027-01-23
- Answers: Which AI service should I sign up for first? · I already pay for ChatGPT Plus - why is that not an API key? · How do I know the key worked? · Can I use models running on my own machine?

Big-AGI starts empty: connecting an AI service is what fills it with models. One key from one service is enough to start: no minimum spend, and a second service costs nothing to add. A key is not a chat subscription: AI services sell their consumer chat product and their API as two accounts with two balances. A ChatGPT Plus or Claude Pro subscription therefore carries no key, and Anthropic [states it directly](https://support.claude.com/en/articles/9876003-i-subscribe-to-a-paid-claude-ai-plan-why-do-i-have-to-pay-separately-for-api-usage-on-console). The key comes from the service's developer console, on its own balance.

## Where to start

Open one of the four the app offers first: [OpenAI](/docs/connect-openai), [Anthropic](/docs/connect-anthropic), [Gemini](/docs/connect-gemini) or [OpenRouter](/docs/connect-openrouter). Want a specific vendor's own models - go to that vendor. Want the fewest steps to a working key - OpenRouter. Want to try without a payment method - [Gemini](/docs/connect-gemini) has a FREE tier, on its own terms about what you send.

Those four are the **Featured** group in the add-service list, and the same four the first-run setup offers. Everything else is one click further. Three steps cover it: create the key in the service's console, paste it into **Models** (`Ctrl + Shift + M`), and that service's models fill the list - the signal it worked ([your first chat](/docs/first-chat)).

## One key, many models

An aggregator does exactly that, and [OpenRouter](/docs/connect-openrouter) is the one in the list: one account, one balance, a catalogue spanning the major vendors' models. Big-AGI carries a one-click handoff for it - **Link OpenRouter Key** in that panel sends you to OpenRouter to authorise and returns with the key installed. The trade is a middleman: one bill, one catalogue, and a list filtered to curated model families by default. A gift icon in the add-service list marks services that publish some models at no charge.

## AI services in the app

**Featured** - [OpenAI](/docs/connect-openai) · [Anthropic](/docs/connect-anthropic) · [Gemini](/docs/connect-gemini) · [OpenRouter](/docs/connect-openrouter)

**Cloud** - [Alibaba Cloud](/docs/connect-alibaba) · [AWS Bedrock](/docs/connect-bedrock) · [Azure OpenAI](/docs/connect-azure) · [Cerebras](/docs/connect-cerebras) · [Cohere](/docs/connect-cohere) · [DeepSeek](/docs/connect-deepseek) · [Groq](/docs/connect-groq) · [Mistral](/docs/connect-mistral) · [Modular](/docs/connect-modular) · [Moonshot AI](/docs/connect-moonshot-ai) · [NVIDIA NIM](/docs/connect-nvidia-nim) · [Perplexity](/docs/connect-perplexity) · [Sakana AI](/docs/connect-sakana) · [Together AI](/docs/connect-together) · [xAI](/docs/connect-xai) · [Z.ai](/docs/connect-zai)

**Local** - [Ollama](/docs/connect-ollama) · [LM Studio](/docs/connect-lmstudio) · [LocalAI](/docs/connect-localai)

Anything outside the wall that speaks the OpenAI API connects too: [custom endpoints](/docs/connect-custom-endpoints). Support for a new service is written in the open-source codebase first and reaches the hosted site on promotion.

## The model for each job

Big-AGI assigns a model per job rather than per service, across everything you have connected:

| Job | Used for | Default |
|---|---|---|
| **Chat** | Conversations - changeable per message, before sending | Auto |
| **Code** | Applying code changes | Auto |
| **Fast** | Titles, summaries, small utility calls | Auto |
| **Vision** | Reading images | Auto |

**Auto** resolves the moment it is read, and a hand-curated pick wins where one exists. Pin a job with the **Default / Model for** buttons in a model's gear; the dropdown above a chat changes that chat only.

## Models on your own machines

[Ollama](/docs/connect-ollama), [LM Studio](/docs/connect-lmstudio) and [LocalAI](/docs/connect-localai) connect like any other service: point Big-AGI at the server's address, and its models join the same list - no key, no account, no per-token bill.

With [Direct Connection](/docs/feature-direct-connection) off, the Big-AGI fast edge servers call the address you gave; a cloud server cannot reach an address on your computer. With it on, your browser calls the address directly - which is why the panel recommends it for local services.

> **Direct Connection works only with your API key stored in the browser**, and with an AI service that permits direct browser calls (CORS). Where it cannot be used, requests route through the Big-AGI fast edge servers instead - everything still works, within the standard upload size and time limits.

Running locally gives you:

- No per-token bill - hardware and electricity instead.
- Work offline, with material that never leaves the machine.
- Nothing metered: a thousand turns cost what one costs.

## Related

- [Keep your key safe](/docs/key-storage)
- [Model settings](/docs/model-settings)
- [Connect any OpenAI-compatible endpoint](/docs/connect-custom-endpoints)
- [Direct Connection](/docs/feature-direct-connection)