HTTP 103 — Early Hints
1xx Informational
What it means
The server is sending Link headers so the browser can start preloading critical resources before the real response is ready.
What to do about it
Nothing to fix. Used well, it can measurably improve Largest Contentful Paint on slow backends.
Where it sits
103 belongs to the 1xx family: The request was received and the process is continuing. These are rarely seen by application code.
HTTP/1.1 103 Early HintsChecking 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);