Google’s Gary Illyes answered a question about which is less worse to use, millions of 404 error pages or 301 redirects. Gary’s answer cleared the air about how to think about each status code.
The question was simple:
“What is less harmful: having millions of 404 error pages or millions of 301 redirects, where sold product pages redirect to the parent listing page?”
The answer was also simple, although it could have gone into more detail.
This is Gary’s answer:
“404 status codes are completely harmless, and so are 301.
You need to decide what’s better for your scenario for and fly with that.”
Status Codes
Gary uses the phrase “status codes” to refer to the 404 and 301 responses.
They are both responses by a server to a request for a webpage (that was made by a browser or bot).