What Is the 401 Status Code? (Unauthorized)

A 401 means the server can't identify you — you haven't proven who you are. That's the key difference from a 403, where the server already knows you but still refuses. The response usually carries a WWW-Authenticate header naming the login scheme the server wants: Basic (username/password), Bearer (a token), and so on. In short: a 401 status code means the request is missing valid authentication credentials.

Scrapers hit a 401 when the page or API requires you to be logged in. Common causes: a missing or expired session cookie (the small token that proves you already logged in), an absent or wrong API key / Bearer token, or a login step the scraper never completed. Some sites also return a 401 instead of a 403 when an anti-bot layer decides the caller isn't a logged-in human.

Give the server the credentials it legitimately asks for: refresh an expired token or add the API key header it expects. More often for scrapers, a 401 on a public page is a bot block in disguise — handle it like a 403: send realistic headers, use a clean residential IP, and present a real-browser fingerprint via Web Access API.