> ## Documentation Index
> Fetch the complete documentation index at: https://developer.box.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Authentication

export const SignupCTA = ({children}) => {
  return <div className="flex flex-wrap items-center gap-4 p-5 rounded-lg border border-gray-200 dark:border-gray-700 my-6" style={{
    background: "linear-gradient(135deg, rgba(0, 97, 213, 0.06), rgba(0, 97, 213, 0.02))"
  }}>
      <div className="flex-1 text-sm leading-relaxed text-gray-700 dark:text-gray-300" style={{
    minWidth: "280px"
  }}>
        {children}
      </div>
      <div className="flex flex-col items-center gap-2">
        <a href="https://account.box.com/signup/developer#ty9l3" className="signup-cta-button inline-flex items-center whitespace-nowrap px-5 py-2 text-sm font-semibold text-white no-underline">
          Get started for free
        </a>
        <a href="https://account.box.com/developers/console" className="signup-cta-login text-xs text-gray-500 dark:text-gray-400 no-underline whitespace-nowrap">
          Already have an account? Log in
        </a>
      </div>
    </div>;
};

Authentication with the Box API uses an Access Token to identify a user. The
way in which an Access Token is acquired depends on the method used to authorize
a user. The type of authorization available to an application depends on the
use-case as well as the type of application that has been created in the developer
console.

<Frame border width="600" center>
  <img src="https://mintcdn.com/box/_IAqcLWo8orUxXr1/images/guides/applications/app-types/authentication-methods.png?fit=max&auto=format&n=_IAqcLWo8orUxXr1&q=85&s=d984d4bcfecbcc0ece84dc19dc489532" alt="Authentication methods" width="503" height="333" data-path="images/guides/applications/app-types/authentication-methods.png" />
</Frame>

<Card href="/guides/authentication/select" arrow title="Learn how to select an authorization type" />

<SignupCTA>
  A free developer account gives you access to the Developer Console, where you can create apps, configure authentication, and generate access tokens.
</SignupCTA>

## Access Tokens for Authentication

Every API endpoint requires a valid and active **Access Token** to make API
calls. An Access Token is a unique string that identifies an authenticated Box
user to the API endpoints.

```sh theme={null}
curl https://api.box.com/2.0/users/me \
    -H "authorization: Bearer EGmDmRVfhfHsqesn5yVYHAqUkD0dyDfk"
```

<Card href="/guides/authentication/tokens" arrow title="Learn more about Access Tokens" />

[oauth2]: /guides/authentication/oauth2

[jwt]: /guides/authentication/jwt

[devtoken]: /guides/authentication/tokens/developer-tokens

[platform-app]: /guides/applications/platform-apps/index

[ccg]: /guides/authentication/client-credentials