Inspect Response Headers

Fetch a URL and inspect all response headers including custom ones.

Code

Utilities

const response = await fetch('https://httpbin.org/response-headers?X-Custom=test&Cache-Control=max-age=3600');

const headers = {};
response.headers.forEach((value, key) => {
  headers[key] = value;
});
headers;

Browser·fetch() may be limited by CORS

Common Response Headers

Header	Purpose
`content-type`	Response format
`content-length`	Size in bytes
`cache-control`	Caching rules
`set-cookie`	Cookie to store
`location`	Redirect URL
`x-ratelimit-*`	Rate limit info

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