Careful! You are browsing documentation for an outdated version of Kong. Go here to browse the documentation for the latest version.

Table of Contents


This document reviews how the proxy_url and portal_gui_url config variables are utilized within the Kong proxy, Dev Portal, and Admin GUI. Below you find a summary of these config variables and their default settings.



The Dev Portal will use this information to build the API endpoint for requests to Kong. By default, the Kong Portal will use the window request host and append the resolved listener port depending on the requested protocol.


Sets CORS Access Origin in regards to requests related to the developer portal (set to * by default). Acts as Dev Portal location reference for Kong, the Admin GUI, and the Dev Portal itself. By default, the Kong Portal will use the window request host and append the resolved listener port depending on the requested protocol.

Default Configuration

The Kong Dev Portal works out of the box:

  1. Start Kong without custom configuration:
kong start
  1. Navigate to (default portal_gui_url. You should see the Default Dev Portal.

  2. Open your developer tools in your browser and click on the network tab.

  3. Refresh the Dev Portal window and inspect the network tab again. Notice that the Kong Portal is making requests to the proxy_url default value:

Custom Configuration

There are cases in which proxy_url and portal_gui_url need to be set to accommodate your network setup. Below you will find an example for a common use case where the Kong proxy and Dev Portal are served via different URLs.

Consider this domain setup:

  • (public facing website)
  • -> (Kong Proxy)
  • -> (public Dev Portal)
  • -> (internal Admin GUI)

proxy_url configuration

With proxy_url set to it’s default value the Dev Portal will make requests to, as proxy_url defaults to window.location when no value is set. As a result the Dev Portal incorrectly requests files from rather than, resulting in an error.

Setting proxy_url to in kong.config will allow the Dev Portal to make requests to the correct location.

proxy_url =

Visiting will now result in a successful render.

portal_gui_url configuration

portal_gui_url has a value of NONE by default. It will appear as empty and commented out in kong.conf:

#portal_gui_url =

When portal_gui_url is not defined:

  • Kong Proxy will set CORS to *, allowing any origin to make requests to the Dev Portal.
  • Admin GUI and Dev Portal use portal_gui_url to reference Dev Portal location. As a result the Admin GUI will reference window.location by default when linking out to the Dev Portal resulting in a redirect to rather than

Setting portal_gui_url to will:

  • Give context to Admin GUI and Dev Portal.
  • Update CORS in the Kong Proxy to only accept Dev Portal requests from the portal_gui_url.

Next: Learn more about our Property References ›