# Big-AGI Data Ownership Guide

Big-AGI is a **client-first** web application, which means it prioritizes speed and data ownership compared to cloud apps.
Your *API keys*, *chat history*, and *settings* live in your
browser's [local storage](https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage), not
on cloud servers.

You can use Big-AGI in two ways:

1. Run it yourself (open-source)
2. Use big-agi.com (hosted service)

This guide explains how the open-source version handles your data. You can verify everything in [the source code](https://github.com/enricoros/big-agi).

## Client-Side Storage

Within Big-AGI almost all chat/keys data is handled client-side in your browser using two
standard browser storage mechanisms:

- **Local Storage**: API keys, settings, and configurations ([learn more](https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage))
- **IndexedDB**: Chat history and larger files ([learn more](https://developer.mozilla.org/en-US/docs/Web/API/IndexedDB_API))

The Big-AGI backend mainly passes requests to AI services (OpenAI, Anthropic, etc.). It doesn't store your data, except for the chat-sharing function if used.

You can see your data in your browser's local storage and IndexedDB - try it yourself:

1. In Chrome: Open DevTools (press F12 on Windows, ⌘ + ⌥ + I on Mac)
2. Click 'Application' > 'Local Storage'
3. See your settings and API keys

![Browser local storage showing API keys and chat data](pixels/data_ownership_local_storage.png)

### Sync for Authenticated Users

Users with accounts on big-agi.com who opt into Sync (a Pro feature) have their entity data - such as conversations and personas - replicated to the server for multi-device access.
Server-side data is isolated per-user using Row Level Security (RLS), ensuring that no other user can access your synced data.
Sync is entirely optional; without it, all data remains local to your browser.

### What This Means For You

Storing data in your browser means:

- Your data stays on **one device/browser only**
- Clearing browser data **erases your chats** - make backups
- Anyone using your browser can see your chats and keys
- Running your own server needs technical skills

### Device Identifier

When you sign in, Big-AGI keeps a _device identifier_ so your devices can be told apart for optional Sync and listed under your account.
It is **server-issued** (a random UUID) and stored in a durable, first-party **httpOnly cookie** (`agi.client-token`) - not created by,
or readable from, page scripts. This identifier:

- Identifies your **client** - one per browser, so a second browser or an installed app on the same machine is a separate device
- Replaces a former localStorage mechanism, see `src/common/stores/store-client.ts` if available in the source code
- Is **not** set for signed-out visitors, and is never used for tracking, advertising, analytics, or telemetry
- Is scoped to your account via Row Level Security, so no other user can see it
- Is a server-set cookie; it resets only if you clear **cookies/site data**


## How Data Flows

AI interactions in Big-AGI, such as chats, AI titles, text to speech, browsing, flow through three components:

1. **Browser** (client/installed App) - Stores your keys & data locally
2. **Backend** (routing server) - Passes requests to AI services
3. **AI Services** - Where the actual AI processing happens

### Self-Deployed Version: Your Infrastructure

You run the server. Your data only leaves when making AI requests.
The keys and chats are under your control and pass through your code, and are sent to
the upstream AI services on a per-request basis.

![data_ownership_local.png](pixels/data_ownership_deployed.png)

### Web Version: Using big-agi.com

Your data passes through the hosted Big-AGI edge network to reach AI services. The keys
and chats pass through Big-AGI's edge network to reach the AI services on a per-request basis,
and then are send to the upstream AI services.

![data_ownership_hosted.png](pixels/data_ownership_hosted.png)

### Direct Connection (Browser → AI Service)

Most AI services offer a **Direct Connection** toggle (under a service's Advanced settings). When enabled, the browser calls the AI provider's API directly, skipping the Big-AGI server entirely.

Benefits:

- **No 4.5 MB upload limit** - the Vercel body-size cap does not apply, so larger attachments and long prompts go through.
- **No 300-second timeout** - the Vercel function timeout does not apply, so long-running generations keep streaming.
- **More privacy** - connection metadata (IP, timestamp, edge region, Vercel telemetry) is not observable by the Big-AGI edge server.

Tradeoff:

- **Slightly more downlink bandwidth**: when traffic passes through the Big-AGI edge, repetitive streaming frames are compacted; direct streams arrive verbatim from the provider.

Availability requires both:

1. The API key is set in your browser (client-side), not via server environment variables. Server-key deployments cannot use Direct Connection because the browser has no credential to send.
2. The AI service allows CORS (browser-origin requests). Most major providers do; Big-AGI sets any extra headers they require.

Direct Connection is a net win on speed, limits, and privacy whenever the provider permits it.

## Security Best Practices

**Basic Security**:

- **Never share API keys**
- **Don't use shared computers**
- Use private browsing for one-off sessions
- Use trusted networks
- Back up your data

**When Running Your Own Server**:

- Use [environment variables](environment-variables.md) for API keys
- Run on trusted infrastructure
- Keep your installation updated

## TL;DR

Your API keys and chats stay in your browser. The server only passes requests to AI services.

Use big-agi.com for convenience, or [run it yourself](installation.md) for full control.

Need help? Join our [Discord](https://discord.gg/MkH4qj2Jp9) or open a [GitHub issue](https://github.com/enricoros/big-agi/issues).