[Home](./index.md) > [@firebase/auth](./auth.md) > [signInWithRedirect](./auth.signinwithredirect.md)
## signInWithRedirect() function
Authenticates a Firebase client using a full-page redirect flow.
Signature:
```typescript
export declare function signInWithRedirect(auth: Auth, provider: AuthProvider, resolver?: PopupRedirectResolver): Promise;
```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| auth | [Auth](./auth.auth.md) | The Auth instance. |
| provider | [AuthProvider](./auth.authprovider.md) | The provider to authenticate. The provider has to be an [OAuthProvider](./auth.oauthprovider.md). Non-OAuth providers like [EmailAuthProvider](./auth.emailauthprovider.md) will throw an error. |
| resolver | [PopupRedirectResolver](./auth.popupredirectresolver.md) | An instance of [PopupRedirectResolver](./auth.popupredirectresolver.md), optional if already supplied to [initializeAuth()](./auth.initializeauth.md) or provided by [getAuth()](./auth.getauth.md). |
Returns:
Promise<never>
## Remarks
To handle the results and errors for this operation, refer to [getRedirectResult()](./auth.getredirectresult.md).
## Example
```javascript
// Sign in using a redirect.
const provider = new FacebookAuthProvider();
// You can add additional scopes to the provider:
provider.addScope('user_birthday');
// Start a sign in process for an unauthenticated user.
await signInWithRedirect(auth, provider);
// This will trigger a full page redirect away from your app
// After returning from the redirect when your app initializes you can obtain the result
const result = await getRedirectResult(auth);
if (result) {
// This is the signed-in user
const user = result.user;
// This gives you a Facebook Access Token.
const credential = provider.credentialFromResult(auth, result);
const token = credential.accessToken;
}
// As this API can be used for sign-in, linking and reauthentication,
// check the operationType to determine what triggered this redirect
// operation.
const operationType = result.operationType;
```