HTTP 303 — See Other
3xx Redirection
What it means
Redirects the client to fetch the result with GET, regardless of the original method. The classic POST-redirect-GET pattern.
What to do about it
Use it after a successful form POST so that a page refresh does not resubmit the form.
Where it sits
303 belongs to the 3xx family: Further action is needed to complete the request — usually following a redirect.
HTTP/1.1 303 See OtherChecking it yourself
# see the status code and headers only
curl -sI https://example.com/path
# follow redirects and print each hop
curl -sIL -o /dev/null -w "%{http_code} %{url_effective}\n" https://example.com/path
# JavaScript
const r = await fetch(url);
console.log(r.status, r.statusText);