HTTP Header Checker

Inspect HTTP response headers from any website. Check status codes, security headers, caching, and more.

HTTP or HTTPS

Common HTTP Headers

Content-Type

Specifies the media type of the resource (e.g., text/html, application/json, image/png).

Cache-Control

Instructs browsers and intermediate caches how to cache the resource.

Server

Identifies the web server software being used (e.g., nginx, Apache, IIS).

Set-Cookie

Sets HTTP cookies to be stored by the client browser.

Strict-Transport-Security

Forces HTTPS connections and prevents downgrade attacks (HSTS).

X-Frame-Options

Prevents clickjacking attacks by controlling iframe embedding.

Content-Security-Policy

Prevents XSS attacks by restricting script sources and other content.

ETag

Unique identifier for a resource version used for caching and validation.

HTTP Status Codes

2xx Success

  • 200 - OK
  • 201 - Created
  • 204 - No Content

3xx Redirection

  • 301 - Moved Permanently
  • 302 - Found
  • 304 - Not Modified

4xx Client Error

  • 400 - Bad Request
  • 401 - Unauthorized
  • 404 - Not Found

5xx Server Error

  • 500 - Internal Error
  • 502 - Bad Gateway
  • 503 - Service Unavailable