HTTP Reference

HTTP 304 Not Modified

Cached content is still valid, so the server returns no new body.

Common Causes

  • Conditional GET with If-None-Match matched current ETag.
  • If-Modified-Since value indicates resource has not changed.
  • Browser cache revalidation request succeeded.

Debugging Notes

  • Inspect cache headers (ETag, Last-Modified, Cache-Control) for consistency.
  • Verify clients properly handle empty body for 304 responses.

Example Response

{
  "status": 304,
  "message": "not modified"
}

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