About this article
This article was created using an automated generation workflow leveraging generative AI. It verifies the HTTP HEAD method and the official curl specifications, organizing the steps to read-only observe the differences from the GET method.
Verification Status: 📘 RFC and official curl specifications verified; live traffic unverified
When you want to check only the headers without downloading the body of a web page,curl -Ican be used. However, the result of a HEAD request does not necessarily mean that GET will behave in the exact same way.
Try it first
curl -I https://example.com/
Observe the HTTP status, Content-Type, Content-Length, and other details.
Next, display the headers using GET as well.
curl -sS -D - -o /dev/null https://example.com/
Check this point
Compare whether the status and headers are identical between HEAD and GET. Differences may occur depending on server implementations or intermediate devices.
Try changing one thing
Change the end of the URL to a non-existent path and see how statuses like 404 change.
Why it matters
Using only HEAD for monitoring or link checking can cause you to overlook discrepancies with the actual GET path. It is easier to understand if you separate their roles: HEAD for lightweight primary verification, and GET for user-equivalent verification.
For professional use
It can be used for initial verification of web migrations, redirects, CDNs, and API connectivity. Before sending heavy traffic to production, limit the target count and frequency, and make sure not to leave tokens for authenticated URLs in logs.
Conclusion
curl -Iis useful, but it is not a "complete substitute for GET." Simply comparing HEAD and GET on the same URL lets you experience those differences firsthand.
Official references
curl manual
RFC 9110 HTTP Semantics
