• Is it a good idea for large websites to host images on a separate subdomain to split server loads?

  In a recent Linkedin post, Google's John Mueller was asked whether hosting images on a separate subdomain in order to simplify Googlebot's job, especially for large sites, is recommended. And, if so, what are the benefits?

John's Answer:

If Google has trouble crawling as much as it wants to crawl due to technical reasons, then splitting the load across subdomains or domains makes sense. Sometimes this makes sense for any kind of static content regardless of Google's crawling (many sites have static content CDNs).

For most sites, this isn't needed. (It won't push Google to crawl more, and more crawling doesn't mean better ranking.)

As John said, "for most sites it isn't needed" — but for some very large sites, splitting a website into subdomains can be a strategic move to improve SEO and distribute server load, but it's important to weigh the pros and cons carefully.

Here are some guidelines for when to split your website into subdomains for SEO and server load:

Scenarios where splitting your website into subdomains might be beneficial:

• Distinctly Different Content:
  • Separate Brands or Product Lines: If you have multiple brands or product lines that are significantly different, separating them into subdomains can help Googlebot better understand the content and categorize it appropriately.
  • Geographically Targeted Content: For businesses with a strong regional focus, using country-specific subdomains (e.g., uk.example.com, de.example.com) can improve local SEO.