Title: CORS error using WP REST API
Last modified: May 31, 2023

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# CORS error using WP REST API

 *  [jeppex](https://wordpress.org/support/users/jeppex/)
 * (@jeppex)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/)
 * Hey there
 * I have set up a wordpress installation at a subdomain of my site. On the main
   domain, I am running a React build that fetches the content from the headless
   WordPress. It all appears to work.
 * However, on every load of the page I get a CORS error:
 * “No ‘Access-Control-Allow-Origin’ header is present on the requested resource.”
 * I mostly get this on just a single endpoint. It is not the same endpoint that
   throws an error, but there appears to be at least one CORS error every time.
 * Under settings I have set wordpress address and site address to the subdomain.
   And I am running https.
 * I have also tried setting the site address to the main domain which gave the 
   same CORS errors. (And in this process I accidentally made a mistake, so I couldn’t
   acces the dashboard, so now both addresses are hardcoded in the function.php 
   as the subdomain. If the site address is the main domain, I cannot access the
   controlpanel..)
 * Any idea of what the issue could be? Any help appreciated 🙂
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fcors-error-using-wp-rest-api%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Moderator [bcworkz](https://wordpress.org/support/users/bcworkz/)
 * (@bcworkz)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/#post-16787139)
 * WP by default does not respond with any Access-Control-Allow-Origin header. If
   your app requires such a header, it can be added through the “wp_headers” filter.
 * To limit the header to API requests, your callback could check if constant `REST_REQUEST`
   is defined and its value is `true`.
 * The ideal value for the header is discussed in [this Mozilla doc page](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS).
   The least restrictive would be `Access-Control-Allow-Origin: *`. (allow any origin)
 *  Thread Starter [jeppex](https://wordpress.org/support/users/jeppex/)
 * (@jeppex)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/#post-16794889)
 * Thank you for your response!
   When I add the `Access-Control-Allow-Origin: *` 
   in the .htaccess, all endpoints seem to fail.
 * However, I noticed that in the console appears as a CORS error, in the network
   tab in dev tools is a 508 loop detected error. Still, only on one endpoint each
   time.
 * Could this be something else than a issue with the headers?
 *  Moderator [bcworkz](https://wordpress.org/support/users/bcworkz/)
 * (@bcworkz)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/#post-16795325)
 * A 508 status suggests a faulty .htaccess directive somewhere. I added the following
   to my .htaccess as a test, it worked as expected without error:
 *     ```
       <IfModule mod_headers.c>
         Header set Access-Control-Allow-Origin "*"
       </IfModule>
       ```
   
 *  Thread Starter [jeppex](https://wordpress.org/support/users/jeppex/)
 * (@jeppex)
 * [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/#post-16798086)
 * Thanks again!
 * But it appeared simply to be faulty code. I actually had a loop in my get requests
   🤦‍♂️
    -  This reply was modified 2 years, 11 months ago by [jeppex](https://wordpress.org/support/users/jeppex/).

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘CORS error using WP REST API’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 4 replies
 * 2 participants
 * Last reply from: [jeppex](https://wordpress.org/support/users/jeppex/)
 * Last activity: [2 years, 11 months ago](https://wordpress.org/support/topic/cors-error-using-wp-rest-api/#post-16798086)
 * Status: not resolved

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