It’s recommended to keep the same URL when converting image file formats
Converting image formats (for example from JPEG to WebP) has the potential to impact existing rankings. Where possible, it’s recommended to keep the same image URLs and just swap out the files. Otherwise, Google will need to discover and index those new URLs in the same way it would for text-based content.
Once Google Processes The Content on a Page URLs Become Less Significant
The words contained in URLs are used as a small factor by Google when ranking a page, but once they are able to process and understand the content on the page the URL doesn’t play as significant a role. This is regardless of the page type, whether it is an AMP page or a traditional web page.
Use 301 Redirects to Inform Google of Your Preferred URL Structure
If you have a mixture of www. and non www. URLs on a site, the best way to inform Google of your preferred URL structure is to add 301 redirects with a consistent preferred domain choice.
Google Will Usually Drop Session IDs from URLs
Instead of choosing a representative URL for a set of URLs with session IDs, Google will usually drop the session ID from the URLs completely if it recognises that they don’t return any unique content.
Removing a Folder Containing Multiple URLs in the URL Removal Tool Considered as a Single Request
Removing a folder containing multiple pages using the URL removal tool will be considered as a single removal request by Google. As there is a limit to the number of requests you can make with the removal tool, John recommends narrowing down to a specific folder or URL structure, as it will save you from having to individually request removals.
Performing URL Rewriting is the Best Way to Change the URL Structure of a Site
If you are changing the URL structure of a website, John recommends keeping the old URLs and rewriting the URLs on the server-side, if possible. This is because, from Google’s point of view, there is very little change and it’s easier to understand the content than having to reprocess all of the new URLs. If you are not able to keep the old URLs, ensure you 301 redirect from the old ones to the new ones. A redirect is a much stronger signal that you are moving content to new URLs than canonicalising them.
Google Treats Escaped & Unescaped Versions of URLs & Links as Equivalent
Escaped versions of URLs and links are treated exactly the same as the unescaped versions by Google.
Google Can Treat Hash URLs as Separate URLs if They Lead to Unique Content
Google usually ignores anything after the hash, but the exceptions to this are hashbang URLs and hash URLs that lead to unique content that isn’t available on the non-hash version of the URL. John recommends that you should avoid relying on this, however.
Keep URLs Under 1,000 Characters in Length
John recommends making sure that URLs are under 1,000 characters in length so that they can be crawled and indexed.