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

# Vercel

<View title="Developer" />

<View title="Federal docs">
  <Danger>
    **This integration is not available in federal environments**

    To learn more, read <a href="/docs/home/infrastructure/federal">LaunchDarkly in federal environments</a>.
  </Danger>
</View>

<View title="EU docs">
  <Danger>
    **This integration is not available in LaunchDarkly's European Union (EU) instance**

    To learn more, read <a href="/docs/home/infrastructure/eu">LaunchDarkly in the European Union (EU)</a>.
  </Danger>
</View>

This topic explains how to use the LaunchDarkly Vercel integration. This integration enables flag evaluation within Vercel Functions. It writes the latest flag data from your configured environment directly to a Vercel Global Config in your account, and syncs later flag or segment changes to that Global Config automatically.

This integration does not connect LaunchDarkly SDK keys to your Vercel projects. If you want SDK keys provisioned and synced automatically as environment variables, read [Vercel Marketplace](/docs/integrations/vercel-marketplace) instead.

You can use the Vercel integration to bootstrap your application with the latest client-side feature flags. This eliminates the initial remote call to LaunchDarkly, providing zero-latency client-side feature flags with no flash of original content or shift in content layout. Evaluating flags within Vercel Functions gives you the same benefit at the server level, without added latency from network requests.

Vercel enforces size limits on Global Config values. Additionally, Vercel charges customers for Vercel Config writes. Each feature flag or segment change in an environment where the integration is installed will incur a Global Config write. Based on these limits, Vercel Enterprise customers and Vercel Pro customers with moderately-sized environments are likely to benefit the most from this integration. To learn more, read Vercel's documentation on [Global Config limits and pricing](https://vercel.com/docs/global-config/global-config-limits#limits).

<Note>
  **This integration requires LaunchDarkly's Vercel SDK**

  You must install and configure the Vercel SDK to use this integration. To learn more, read [Vercel SDK reference](/docs/sdk/edge/vercel).
</Note>

## Install a Vercel integration

For the Vercel integration to work, you need a Vercel account with at least one project.

You can install a Vercel integration on the [LaunchDarkly](https://vercel.com/integrations/launchdarkly) page in the Vercel integrations marketplace.

<Note>
  **Vercel Global Config size limits**

  Vercel Global Configs enforce size limits that might be smaller than your LaunchDarkly flag data in a given environment. We recommend using a dedicated Global Config for LaunchDarkly environments.

  To learn more, read about [Global Config limits and pricing](https://vercel.com/docs/global-config/global-config-limits).
</Note>

To install a Vercel integration for your environment:

1. Navigate to [Vercel's Integrations page for LaunchDarkly](https://vercel.com/integrations/launchdarkly).

2. Click **Add Integration**.

3. Select the Vercel account that you would like to connect to LaunchDarkly.

4. Choose the projects within that account that you would like LaunchDarkly to have access to.

5. Click **Continue**.

6. Review the permissions that this integration requires. Then click **Add Integration**. The LaunchDarkly configuration screen appears:

   <Frame caption="The LaunchDarkly authorization panel.">
     <img src="https://mintcdn.com/launchdarkly/ltwUrD5AmJ696YaX/images/__third_party/vercel-auth-panel.png?fit=max&auto=format&n=ltwUrD5AmJ696YaX&q=85&s=3b492232eb239398cf0f689ce0e24c61" alt="The LaunchDarkly authorization panel." width="1112" height="832" data-path="images/__third_party/vercel-auth-panel.png" />
   </Frame>

7. Click **Authorize** to grant access to the LaunchDarkly integration.

8. Enter a **Name** for the integration. This integration is specific to this combination of your LaunchDarkly environment and the Vercel Global Config ID.

9. Choose an environment from the **Environment** menu. Your data appears in your Global Config under the key `LD-Env-{{environment client-side ID}}`.

10. Choose a Global Config from the **Global Config** menu. Alternatively, click **Click to create new global config** to create a new global config.

11. Click **Save configuration**.

    <Frame caption="The LaunchDarkly &#x22;Vercel Integration&#x22; panel.">
      <img src="https://mintcdn.com/launchdarkly/ltwUrD5AmJ696YaX/images/__third_party/vercel-create-integration.png?fit=max&auto=format&n=ltwUrD5AmJ696YaX&q=85&s=389964c4fd751c8ad5c6d51b4d398555" alt="The LaunchDarkly &#x22;Vercel Integration&#x22; panel." width="778" height="589" data-path="images/__third_party/vercel-create-integration.png" />
    </Frame>

## Configure the LaunchDarkly Vercel integration

You can manage existing Vercel integrations from the same [LaunchDarkly listing page](https://vercel.com/integrations/launchdarkly) in the Vercel integrations marketplace.

To manage an existing Vercel integration:

1. In Vercel, navigate to the **Integrations** page.

2. Find your LaunchDarkly integration and click **Manage**.

3. Click **Configure**. The LaunchDarkly configuration panel appears.

   <Frame caption="The LaunchDarkly edit configuration panel.">
     <img src="https://mintcdn.com/launchdarkly/ltwUrD5AmJ696YaX/images/__third_party/vercel-edit-configuration.png?fit=max&auto=format&n=ltwUrD5AmJ696YaX&q=85&s=28a53dda78e28ae40a6005e14c49ce9b" alt="The LaunchDarkly edit configuration panel." width="1214" height="418" data-path="images/__third_party/vercel-edit-configuration.png" />
   </Frame>

4. Click **Edit** to modify the integration. You can change the configuration name or select another Global Config destination to export to.

5. Click **Save**.

## Uninstall the LaunchDarkly Vercel integration

To uninstall an existing Vercel integration:

1. Navigate to the **Integrations** page in Vercel.

2. Find your LaunchDarkly integration and click **Manage**.

3. Click **Configure**. The LaunchDarkly configuration panel appears.

   <Frame caption="The LaunchDarkly edit configuration panel.">
     <img src="https://mintcdn.com/launchdarkly/ltwUrD5AmJ696YaX/images/__third_party/vercel-edit-configuration.png?fit=max&auto=format&n=ltwUrD5AmJ696YaX&q=85&s=28a53dda78e28ae40a6005e14c49ce9b" alt="The LaunchDarkly edit configuration panel." width="1214" height="418" data-path="images/__third_party/vercel-edit-configuration.png" />
   </Frame>

4. Click **Delete** to remove each integration configuration.

5. Return to the Vercel integration page.

6. Click **Remove Integration**.

<Note>
  **Deleting integration configurations**

  Removing the integration from your Vercel account does not remove any existing integration configurations. Follow the steps above to delete them as part of the removal process. If you have forgotten to do so, you can still delete configurations from the LaunchDarkly **Integrations** page.
</Note>