Sign in with Kakao

To enable Kakao Auth for your project, you need to set up a Kakao OAuth application and add the application credentials to your Supabase Dashboard.

Overview

Kakao OAuth consists of six broad steps:

Create and configure your app in the Kakao Developers Portal.
Obtain a REST API key - this serves as the client_id.
Obtain a Kakao Login Client Secret code - this serves as the client_secret.
Configure additional settings in the Kakao Developers Portal.
Add your client id and client secret keys to your Supabase Project.
Add the sign-in code to your Supabase JS Client App.

Access your Kakao Developer account

Go to Kakao Developers Portal.
Click on Login at the top right to sign in.

Kakao Developers Portal

Create and configure your app

Go to App.
Click on Create app at the top.
Fill out your app information:
- App icon.
- App name.
- Company name.
- Category.
- App primary domain.
Click Save at the bottom right.

Obtain a REST API key

This serves as the client_id when you make API calls to authenticate the user.

Go to App.
Click on your app.
Go to App Settings > App > Platform Key.
In the Platform Key section is REST API key. This will become your client_id later.

Find your callback URL

The next step requires a callback URL, which looks like this: https://<project-ref>.supabase.co/auth/v1/callback

Go to your Supabase Project Dashboard
Click on the Authentication icon in the left sidebar
Click on Sign In / Providers under the Configuration section
Click on Kakao from the accordion list to expand and you'll find your Callback URL, you can click Copy to copy it to the clipboard

Local development

When testing OAuth locally with the Supabase CLI, ensure your OAuth provider is configured with the local Supabase Auth callback URL:

http://localhost:54321/auth/v1/callback

If this callback URL is missing or misconfigured, OAuth sign-in may fail or not redirect correctly during local development.

See the local development docs for more details.

For testing OAuth locally with the Supabase CLI see the local development docs.

To add a callback URL on Kakao, go to App Settings > App > Platform Key.
Click on the REST API key you want to use.
In the edit page, enter your callback URL in the Kakao Login Redirect URI field.
Click Save in the bottom right.

Obtain a client secret

Go to App Settings > App > Platform Key.
Click on the REST API key you want to use.
Note the Kakao Login Client Secret code. This serves as a client_secret for your Supabase project.
Make sure you activate Kakao Login Client Secret.

Additional configurations on Kakao Developers portal

Go to Product Settings > Kakao Login > General.
Set State to "ON" in the Usage settings section to enable Kakao Login.
Go to Product Settings > Kakao Login > Consent Items.
Set the following scopes under the Consent Items:
- account_email (optional)
- profile_image
- profile_nickname

If you don't need an email address (or account_email isn't available for your app), you can omit account_email and enable Allow users without an email in the Supabase Kakao provider settings.

Kakao consent items configuration

Note

In the Kakao Developers Portal, the "account_email" consent item is only available for apps that are registered as "Biz App". To convert your app to a "Biz App", go to App Settings > App > General, and complete the required fields in the Business Information section.

Add your OAuth credentials to Supabase

Go to your Supabase Project Dashboard
In the left sidebar, click the Authentication icon (near the top)
Click on Providers under the Configuration section
Click on Kakao from the accordion list to expand and turn Kakao Enabled to ON
Enter your Kakao Client ID and Kakao Client Secret saved in the previous step
Click Save

If you did not request account_email in Kakao, enable Allow users without an email in the Kakao provider settings.

JavaScript

Flutter

Kotlin

Note

Make sure you're using the right supabase client in the following code.

If you're not using Server-Side Rendering or cookie-based Auth, you can directly use the createClient from @supabase/supabase-js. If you're using Server-Side Rendering, see the Server-Side Auth guide for instructions on creating your Supabase client.

When your user signs in, call signInWithOAuth() with kakao as the provider:

import { createClient } from '@supabase/supabase-js'

const supabase = createClient('https://your-project-id.supabase.co', 'sb_publishable_...')

// ---cut---
async function signInWithKakao() {
  const { data, error } = await supabase.auth.signInWithOAuth({
    provider: 'kakao',
  })
}

When your user signs in, call signInWithOAuth() with kakao as the provider:

Future<void> signInWithKakao() async {
  await supabase.auth.signInWithOAuth(
    OAuthProvider.kakao,
    redirectTo: kIsWeb ? null : 'my.scheme://my-host', // Optionally set the redirect link to bring back the user via deeplink.
    authScreenLaunchMode:
        kIsWeb ? LaunchMode.platformDefault : LaunchMode.externalApplication, // Launch the auth screen in a new webview on mobile.
  );
}

When your user signs in, call signInWith(Provider) with Kakao as the Provider:

suspend fun signInWithKakao() {
	supabase.auth.signInWith(Kakao)
}

When your user signs in, call SignIn() with Provider.Kakao as the provider:

var state = await supabase.Auth.SignIn(Provider.Kakao);
var signInUrl = state.Uri;

For a PKCE flow, for example in Server-Side Auth, you need an extra step to handle the code exchange. When calling signInWithOAuth, provide a redirectTo URL which points to a callback route. This redirect URL should be added to your redirect allow list.

Client

Server

In the browser, signInWithOAuth automatically redirects to the OAuth provider's authentication endpoint, which then redirects to your endpoint.

import { createClient, type Provider } from '@supabase/supabase-js';
const supabase = createClient('https://your-project-id.supabase.co', 'sb_publishable_...')
const provider = 'provider' as Provider

// ---cut---
await supabase.auth.signInWithOAuth({
  provider,
  options: {
    redirectTo: `http://example.com/auth/callback`,
  },
})

In the server, you need to handle the redirect to the OAuth provider's authentication endpoint. The signInWithOAuth method returns the endpoint URL, which you can redirect to.

Caution

Use a server client from @supabase/ssr, and send its cookies with the redirect. signInWithOAuth stores the PKCE code verifier in a cookie. When that Set-Cookie header doesn't reach the browser, the callback can't exchange the code for a session.

import { createServerClient, parseCookieHeader, serializeCookieHeader } from '@supabase/ssr'
import type { Provider } from '@supabase/supabase-js'

// A route handler that receives the incoming Request
async function handler(request: Request) {
  const headers = new Headers()
  const provider = 'provider' as Provider

  const supabase = createServerClient('https://your-project-id.supabase.co', 'sb_publishable_...', {
    cookies: {
      getAll() {
        return parseCookieHeader(request.headers.get('Cookie') ?? '') as {
          name: string
          value: string
        }[]
      },
      setAll(cookiesToSet, cacheHeaders) {
        cookiesToSet.forEach(({ name, value, options }) =>
          headers.append('Set-Cookie', serializeCookieHeader(name, value, options))
        )
        Object.entries(cacheHeaders).forEach(([key, value]) => headers.set(key, value))
      },
    },
  })

  const { data, error } = await supabase.auth.signInWithOAuth({
    provider,
    options: {
      redirectTo: 'http://example.com/auth/callback',
    },
  })

  if (error) {
    throw error
  }

  // Redirect with `headers` so the browser stores the code verifier cookie.
  // Frameworks usually wrap this, for example `redirect(data.url, { headers })` in Remix.
  headers.set('Location', data.url)
  return new Response(null, { status: 303, headers })
}

When your framework sets cookies on the response for you, such as cookies() in Next.js or event.cookies in SvelteKit, write to that API in setAll instead. The cookie is then already on the response, and the redirect needs no extra headers.

At the callback endpoint, handle the code exchange to save the user session.

Next.js

SvelteKit

Astro

Remix

Express

Create a new file at app/auth/callback/route.ts and populate with the following:

import { NextResponse } from 'next/server'

// The client you created from the Server-Side Auth instructions
import { createClient } from '@/utils/supabase/server'

export async function GET(request: Request) {
  const { searchParams, origin } = new URL(request.url)
  const code = searchParams.get('code')
  // if "next" is in param, use it as the redirect URL
  let next = searchParams.get('next') ?? '/'
  if (!next.startsWith('/')) {
    // if "next" is not a relative URL, use the default
    next = '/'
  }

  if (code) {
    const supabase = await createClient()
    const { error } = await supabase.auth.exchangeCodeForSession(code)
    if (!error) {
      const forwardedHost = request.headers.get('x-forwarded-host') // original origin before load balancer
      const isLocalEnv = process.env.NODE_ENV === 'development'
      if (isLocalEnv) {
        // we can be sure that there is no load balancer in between, so no need to watch for X-Forwarded-Host
        return NextResponse.redirect(`${origin}${next}`)
      } else if (forwardedHost) {
        return NextResponse.redirect(`https://${forwardedHost}${next}`)
      } else {
        return NextResponse.redirect(`${origin}${next}`)
      }
    }
  }

  // return the user to an error page with instructions
  return NextResponse.redirect(`${origin}/auth/auth-code-error`)
}

Create a new file at src/routes/auth/callback/+server.js and populate with the following:

import { redirect } from '@sveltejs/kit'

export const GET = async (event) => {
  const {
    url,
    locals: { supabase },
  } = event
  const code = url.searchParams.get('code')
  const next = url.searchParams.get('next') ?? '/'

  if (code) {
    const { error } = await supabase.auth.exchangeCodeForSession(code)
    if (!error) {
      redirect(303, `/${next.slice(1)}`)
    }
  }

  // return the user to an error page with instructions
  redirect(303, '/auth/auth-code-error')
}

Create a new file at src/pages/auth/callback.ts and populate with the following:

import { createServerClient, parseCookieHeader } from '@supabase/ssr'
import { type APIRoute } from 'astro'

export const GET: APIRoute = async ({ request, cookies, redirect }) => {
  const requestUrl = new URL(request.url)
  const code = requestUrl.searchParams.get('code')
  const next = requestUrl.searchParams.get('next') || '/'

  if (code) {
    const supabase = createServerClient(
      import.meta.env.PUBLIC_SUPABASE_URL,
      import.meta.env.PUBLIC_SUPABASE_PUBLISHABLE_KEY,
      {
        cookies: {
          getAll() {
            return parseCookieHeader(Astro.request.headers.get('Cookie') ?? '')
          },
          setAll(cookiesToSet, _headers) {
            cookiesToSet.forEach(({ name, value, options }) =>
              Astro.cookies.set(name, value, options)
            )
          },
        },
      }
    )

    const { error } = await supabase.auth.exchangeCodeForSession(code)

    if (!error) {
      return redirect(next)
    }
  }

  // return the user to an error page with instructions
  return redirect('/auth/auth-code-error')
}

Create a new file at app/routes/auth.callback.tsx and populate with the following:

import { redirect, type LoaderFunctionArgs } from '@remix-run/node'
import { createServerClient, parseCookieHeader, serializeCookieHeader } from '@supabase/ssr'

export async function loader({ request }: LoaderFunctionArgs) {
  const requestUrl = new URL(request.url)
  const code = requestUrl.searchParams.get('code')
  const next = requestUrl.searchParams.get('next') || '/'
  const responseHeaders = new Headers()

  if (code) {
    const supabase = createServerClient(
      process.env.SUPABASE_URL!,
      process.env.SUPABASE_PUBLISHABLE_KEY!,
      {
        cookies: {
          getAll() {
            return parseCookieHeader(request.headers.get('Cookie') ?? '')
          },
          setAll(cookiesToSet, cacheHeaders) {
            cookiesToSet.forEach(({ name, value, options }) =>
              responseHeaders.append('Set-Cookie', serializeCookieHeader(name, value, options))
            )
            Object.entries(cacheHeaders).forEach(([key, value]) => responseHeaders.set(key, value))
          },
        },
      }
    )

    const { error } = await supabase.auth.exchangeCodeForSession(code)

    if (!error) {
      return redirect(next, { headers: responseHeaders })
    }
  }

  // return the user to an error page with instructions
  return redirect('/auth/auth-code-error', { headers: responseHeaders })
}

Create a new route in your express app and populate with the following:

...
app.get("/auth/callback", async function (req, res) {
  const code = req.query.code
  const next = req.query.next ?? "/"

  if (code) {
    const supabase = createServerClient(
      process.env.SUPABASE_URL,
      process.env.SUPABASE_PUBLISHABLE_KEY, {
    cookies: {
      getAll() {
        return parseCookieHeader(req.headers.cookie ?? '')
      },
      setAll(cookiesToSet, headers) {
        cookiesToSet.forEach(({ name, value, options }) =>
          res.appendHeader('Set-Cookie', serializeCookieHeader(name, value, options))
        )
        Object.entries(headers).forEach(([key, value]) =>
          res.setHeader(key, value)
        )
      },
    },
  })
    await supabase.auth.exchangeCodeForSession(code)
  }

  res.redirect(303, `/${next.slice(1)}`)
})

JavaScript

Flutter

Kotlin

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

async function signOut() {
  const { error } = await supabase.auth.signOut()
}

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

Future<void> signOut() async {
  await supabase.auth.signOut();
}

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

suspend fun signOut() {
	supabase.auth.signOut()
}

When your user signs out, call SignOut() to remove them from the browser session and any objects from local storage:

await supabase.Auth.SignOut();

Kakao Login JS SDK is an official Kakao SDK for authenticating Kakao users on websites.

Exchange the authorization code returned by Kakao API for an ID Token.

For example, this code shows a how to get ID Token:

const requestUrl = new URL(request.url);
const code = requestUrl.searchParams.get('code');

if (code) {
  const res = await fetch('https://kauth.kakao.com/oauth/token', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded;charset=utf-8',
    },
    body: new URLSearchParams({
      grant_type: 'authorization_code',
      client_id: '<CLIENT_ID>',
      redirect_uri: '<url>/api/auth/kakao/oidc',
      code,
      client_secret: '<CLIENT_SECRET>',
    }),
  });

  const {id_token} = await res.json();
}

Use the ID Token to sign in:

const res = await auth.signInWithIdToken({
  provider: 'kakao',
  token: id_token,
});

Configuration

Set State to "ON" under OpenID Connect Activation on the Kakao Developers portal.
Add openid to scope along with the scope values you wish to obtain consent for.

Resources

Kakao Developers Portal.

Overview

Access your Kakao Developer account

Create and configure your app

Obtain a REST API key

Find your callback URL

Local development

Obtain a client secret

Additional configurations on Kakao Developers portal

Add your OAuth credentials to Supabase

Add sign-in code to your client app

Using Kakao Login JS SDK

Configuration

Resources