Response · Response header

Allow

Which HTTP methods the target resource supports.

What is Allow?

Sent on 405 Method Not Allowed responses to tell the client which methods are valid, and on OPTIONS responses to advertise capabilities.

Set on 405 responses.

Allow: GET, POST, HEAD

RFC 9110 §10.2.1

What is the Allow HTTP header?

Sent on 405 Method Not Allowed responses to tell the client which methods are valid, and on OPTIONS responses to advertise capabilities.

Is Allow a request or response header?

Allow is a response header — the server sends it to the client. Set on 405 responses.

What does a Allow header look like?

A typical Allow header looks like: Allow: GET, POST, HEAD.

Location

The redirect target (3xx) or newly created resource URL (201).

Retry-After

How long the client should wait before retrying.

Server

Identifies the server software.

Date

When the response was generated.

Link

Serialized <link> relationships as an HTTP header.