Send Custom Headers

Send an HTTP request with custom headers and inspect them in the response.

Code

Utilities

const response = await fetch('https://httpbin.org/headers', {
  headers: {
    'X-Custom-Header': 'my-value',
    'X-Request-Id': '12345',
    'Accept-Language': 'en-US'
  }
});
await response.json();

Browser·fetch() may be limited by CORS

Common Headers

Header	Purpose
`Authorization`	Auth tokens
`X-API-Key`	API authentication
`X-Request-Id`	Request tracing
`Accept-Language`	Preferred language
`Cache-Control`	Caching directives

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