204 No Content

Success: the request was received, understood and accepted.

When a server should send it. When the action succeeded and there is nothing to send back: a DELETE, a saved setting, an autosave or a beacon. A 204 must not have a body; anything after the headers is ignored or breaks the connection.

Common causes. A DELETE, a saved form with nothing to show, or an analytics beacon.

What to do. Nothing. Do not try to parse a body; there is none.

Browsers and HTTP clients. Browsers stay on the current page when a link or form gets a 204, which is why it suits background actions. fetch() gives an empty body, so calling response.json() on it throws.

Google Search. Google gets no content to index; Search Console may report the URL as a soft 404. Source: Google Search Central, How HTTP status codes, and network and DNS errors affect Google Search.

Caching. Cacheable by default (RFC 9110 section 15.1). With no Cache-Control or Expires header, a cache may still store it and reuse it for a heuristic period, often 10% of the time since Last-Modified, so set Cache-Control explicitly if that is not what you want.

HTTP/1.1 204 No Content

(no body)

location /example {
    return 204;
}

http_response_code(204);
exit;

res.writeHead(204);
res.end();

# in a view function
return '', 204