HTTP - OPTIONS Request Method

1 - About

OPTIONS is a request method used in CORS procedure (ie the the “pre-flight” request) asking the server for the CORS headers, but without data.

3 - Example

// The content type is important to see the options request
fetch('', {
    mode: 'cors',
    headers: {
      'content-type': 'application/json'

  • Open the devtool, you should see on the console, the following error.

Access to fetch at '' from origin '' 
has been blocked by CORS policy: 
Response to preflight request doesn't pass access control check: 
No 'Access-Control-Allow-Origin' header is present on the requested resource. 
If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

  • And in the network tab, you should see the OPTIONS request.


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