Auth

Anonymous Sign-Ins

Create and use anonymous users to authenticate with Supabase

Enable Anonymous Sign-Ins to build apps which provide users an authenticated experience without requiring users to enter an email address, password, use an OAuth provider or provide any other PII (Personally Identifiable Information). Later, when ready, the user can link an authentication method to their account.

Anonymous sign-ins can be used to build:

  • E-commerce applications, such as shopping carts before check-out
  • Full-feature demos without collecting personal information
  • Temporary or throw-away accounts

Sign in anonymously

Convert an anonymous user to a permanent user

Converting an anonymous user to a permanent user requires linking an identity to the user. This requires you to enable manual linking in your Supabase project.

Access control

An anonymous user assumes the authenticated role just like a permanent user. You can use row-level security (RLS) policies to differentiate between an anonymous user and a permanent user by checking for the is_anonymous claim in the JWT returned by auth.jwt():


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create policy "Only permanent users can post to the news feed"
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on news_feed as restrictive for insert
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to authenticated
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with check ((select (auth.jwt()->>'is_anonymous')::boolean) is false );
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create policy "Anonymous and permanent users can view the news feed"
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on news_feed for select
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to authenticated
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using ( true );

Resolving identity conflicts

Depending on your application requirements, data conflicts can arise when an anonymous user is converted to a permanent user. For example, in the context of an e-commerce application, an anonymous user would be allowed to add items to the shopping cart without signing up / signing in. When they decide to sign-in to an existing account, you will need to decide how you want to resolve data conflicts in the shopping cart:

  1. Overwrite the items in the cart with those in the existing account
  2. Overwrite the items in the cart with those from the anonymous user
  3. Merge the items in the cart together

Abuse prevention and rate limits

Since anonymous users are stored in your database, bad actors can abuse the endpoint to increase your database size drastically. It is strongly recommended to enable invisible Captcha or Cloudflare Turnstile to prevent abuse for anonymous sign-ins. An IP-based rate limit is enforced at 30 requests per hour which can be modified in your dashboard. You can refer to the full list of rate limits here.

Automatic cleanup

Automatic cleanup of anonymous users is currently not available. Instead, you can delete anonymous users from your project by running the following SQL:


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-- deletes anonymous users created more than 30 days ago
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delete from auth.users
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where is_anonymous is true and created_at < now() - interval '30 days';

Resources