> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-en/sdk/domains-api/tossauth/tossauth.login.md).

# TossAuth.login

> Functional API `appLogin`You can use the same function with this as well.

### Feature description

Log in with Toss authentication. Once login is complete, you’ll be taken back to the Toss app. Returned `authorizationCode`and `referrer`Send it to the server to continue the login process.

### Type

```ts
TossAuth.login(): Promise<AppLoginResponse>;
```

**Params**

None

**Response**

```ts
type AppLoginResponse = {
  authorizationCode: string;
  referrer: "DEFAULT" | "SANDBOX";
};
```

### Example code

```js
import { TossAuth } from "@apps-in-toss/web-framework";

const button = document.querySelector("#login-button");

button.addEventListener("click", async () => {
  try {
    const { authorizationCode, referrer } = await TossAuth.login();
    // Send authorizationCode and referrer to the server
  } catch (error) {
    console.error(error);
  }
});
```


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