> ## Documentation Index
> Fetch the complete documentation index at: https://auth0-feat-sdk-reference-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# createAuth0Client

```typescript
createAuth0Client(options: Auth0ClientOptions & { refreshTokenMode: "online"; useDpop: true; useRefreshTokens: true }): Promise<Auth0Client>
```

Online mode requires `useRefreshTokens: true` and `useDpop: true`, enforced here at
compile time. Dynamic values, casts, and plain JS are covered by the runtime check in
the `Auth0Client` constructor.

## Parameters

<ResponseField name={"options"} type={"Auth0ClientOptions & { refreshTokenMode: \"online\"; useDpop: true; useRefreshTok…"} required>
  Type: [Auth0ClientOptions](/docs/sdk/typescript/interfaces/Auth0ClientOptions)
</ResponseField>

## Returns

`Promise<Auth0Client>`

```typescript
createAuth0Client(options: Auth0ClientOptions & { refreshTokenMode: "offline" }): Promise<Auth0Client>
```

Asynchronously creates the Auth0Client instance and calls `checkSession`.

**Note:** There are caveats to using this in a private browser tab, which may not silently authenticate
a user on page refresh. Please see [the checkSession docs](https://auth0.github.io/auth0-spa-js/classes/Auth0Client.html#checksession) for more info.

## Parameters

<ResponseField name={"options"} type={"Auth0ClientOptions & { refreshTokenMode: \"offline\" }"} required>
  The client options

  Type: [Auth0ClientOptions](/docs/sdk/typescript/interfaces/Auth0ClientOptions)
</ResponseField>

## Returns

`Promise<Auth0Client>`

An instance of Auth0Client