Domain factors describe a whole site: its name, history, hosting, uptime and security. Google's ranking systems "work on the page level", but "site-wide signals and classifiers are also used." Much domain folklore comes from patents and correlation studies rather than Google's documentation, so the table sorts each factor by what Google Search Central 1 says today.
| Factor | Status in Google's documentation | What to do |
|---|---|---|
| Domain age | Unconfirmed | Ignore when buying a domain |
| Keywords in the domain | Confirmed, very small | Choose a memorable brand |
| Registration length, WHOIS privacy | Unconfirmed | Decide on cost and privacy |
| Country-code TLD | Confirmed, for country targeting | Use only when serving one country |
| Server location | Confirmed, weak | Host wherever is fastest |
| Domain Authority, TrustRank scores | Not a ranking factor | Earn real links and mentions |
| Uptime | Confirmed: failing URLs drop out | Keep outages short, send 503 |
| HTTPS | Not a direct factor today | Serve HTTPS anyway |
| Hacked content | Confirmed: warnings or removal | Monitor and fix fast |