If-None-Match

Conditional request: if ETag matches, server returns 304 Not Modified. Saves bandwidth.

Request

Syntax

If-None-Match: <etag> | *

Example values

ValueExplanation
"33a64df551425fcc55e4d42a148795d9f25f89d4"Match specific ETag
*Match any representation

cURL usage

curl -H 'If-None-Match: "etag-value"' https://api.example.com/users/1

Common mistakes

Sending stale ETag; * used for upload/create, not GET.

Related headers

Tools

HTTP Header Viewer →