What does a cURL HEAD request do?

A cURL HEAD request (invoked via curl -I or curl --head) requests only the HTTP response headers from a server without downloading the response body, making it ideal for checking HTTP status codes, redirection targets, content types, and caching headers with minimal network bandwidth.

How do I follow HTTP redirects in cURL?

To follow 301, 302, or 307 redirects while fetching headers, include the -L (or --location) flag alongside -I (e.g. curl -IL https://example.com).

What security headers should I look for in HTTP responses?

Essential HTTP security headers include Strict-Transport-Security (HSTS), Content-Security-Policy (CSP), X-Frame-Options (clickjacking defense), X-Content-Type-Options (MIME-sniffing protection), and Referrer-Policy.

cURL HEAD Request Generator & HTTP Header Inspector

Why Use cURL HEAD Requests?

A standard HTTP GET request downloads both response headers and the entire payload body (which could be megabytes or gigabytes in size). In contrast, the HTTP HEAD method instructs the target web server to return the exact same HTTP headers as GET, but without sending the response body.

Primary Use Cases for curl -I

Verify URL Redirections: Confirm whether legacy URLs correctly resolve via 301 Moved Permanently or 308 Permanent Redirect to prevent SEO link equity degradation.
Check Content-Length & MIME Types: Inspect file size and content type before downloading large assets or binaries.
Verify Cache Invalidation: Check ETag, Age, and Cache-Control response directives on CDN edge nodes (Cloudflare, Fastly, AWS CloudFront).
Security Compliance Auditing: Quickly audit HTTPS security headers across hundreds of enterprise endpoints.

Frequently Asked Questions

What is the difference between curl -I and curl -X HEAD?

While both initiate a HEAD request, curl -I (or --head) tells cURL to fetch headers only and automatically sets the method to HEAD. Using curl -X HEAD sets the method string to HEAD but does not suppress body reading if the server misbehaves and sends content. Therefore, curl -I is always recommended.

Can web servers block HEAD requests?

Occasionally, poorly configured web application firewalls (WAF) or APIs return a 405 Method Not Allowed for HEAD requests. In such scenarios, use curl -s -D - -o /dev/null https://example.com to issue a normal GET request while dumping only headers to stdout.

cURL HEAD Request & Header Inspector

Why Use cURL HEAD Requests?

Primary Use Cases for curl -I

Frequently Asked Questions