Google does not index all your web pages as they would not rank in the search results
When your website serves a server-rendered page to Google and this page contains JavaScript, make sure that if the JavaScript breaks, it does not affect i.e. remove or reload your content. Otherwise, it interferes with Google indexing that particular web page.
Use rel=prev/next for pagination only
Google only indexes and ranks your web pages based only on the content that it can see.
Valid structured markup data does not guarantee that it will always be shown in Google search results.
Make small step-by-step changes to your website than wholesale changes in one go as this confuses Google
If one part of a website has serious technical errors, it could negatively affect the whole website.
Use 304 http status codes for If-Modified-Since requests only
Server errors (50X) can affect how often Google crawls your website.
Google can find and index content hidden in tabs.
If your website is using shared hosting, and another website sharing the same IP as yours get hit by Google, this should not negatively affect your website.
A website migration is not a good way to get rid of a manual action.
Having a Google Ads account with running ads or adding Google Analytics to your website will not impact your website positions in the organic search results.
Use the rel=NoFollow attribute only for websites you do not want to be associated with.
Pages disallowed in robots.txt can still be indexed and shown in Google search because there are many Backlinks pointing to the page
Many comments on blog posts do not boost rankings
Google cannot read text on images. Use the ALT attribute to help Google to understand the image and its text.
Google treats a website that uses a CDN like any other website
A noindex X-Robots-Tag in HTTP header of your XML sitemap does not influence crawl frequency of that particular sitemap
Embedding images on web pages e.g. from Instagram could affect how Google crawls and indexes that web page.
If you’re using infinite scroll, make sure that Google can still see the links to individual page
Googlebot cannot click button or submit forms on your website, etc. Make sure to describe and label and interactive objects in your HTML.
Ranking Factors
Google doesn’t use MOZs domain authority metric or AHREFs URL rating as a ranking factor.
Using keywords in the URL is not a critical ranking factor but influential as it sends a signal to Google about the relevance of a given web page.
Google nevers count the words in a blog post and use it as a ranking factor. Use as many words to make the content useful to your users.
Using AMP improves the speed of your website but itself it is not a ranking factor.
Using photos that are also found on other websites will not harm your website rankings but will affect image search rankings.
Invalid HTML and/or CSS does not directly impact your rankings but in some cases will hurt user experience which indirectly hurts your rankings.
The age of your website domain is not a ranking factor
Any changes you make to your content means Google will have to re-evaluate the content for new signals that could boost the web page’s ranking in the search results.
There is no technical way to stop your website from ranking for negative keywords
Google stopped using meta keywords as a ranking factor a long time ago.
Including your brand name in title tags will not boost your rankings
Invalid structured data markup on a website does not negatively impact its rankings
Google Algorithm Updates
Google algorithmic changes are usually concentrated not on particular industries but on the searches people make. But these two spheres are closely connected, which means that sometimes algorithms updates happen to influence some industries more than others.
Google oftens tests Google search algorithm updates using Quality Raters Guidelines before a wide roll out
Website Structure
It doesn’t matter for Google which website URL structure you choose so long it makes sense for your users and business
Internal linking is more important than a web address URL structure
Manual Action/Penalties
If your website has been penalized by Google i.e. a manual action, you will receive a notification via Google Search Console (GSC).
Redirects
Remember to redirect the old resources web address URLs to the new web address URLs when making design changes to your website.
Use of 301 or 302 redirects does not lose your web pages link juice (link equity) but signals to Google where link juice (link equity) should go.
In some instances, Google will treat a 302 (temporary) redirect the same as a 301 (Permanent) redirect if the 302 redirect has been in place for a long time.
Buying expired domains with the hope to use redirects to get link juice (link equity) is against Google Webmaster Guidelines.
Keep redirects in place until Google indexes the final URL.
Mobile-Friendly
Mobile usability issues notifications from Google do not mean your web pages are not mobile-friendly
Its best practice to have a mobile-friendly website even though data shows you do not have mobile users.
Sitemaps
No need to have separate XML sitemaps for images and web pages vs a single sitemap listing them all together. Both approaches work since Google combines them all before processing them.
The web address URLs order in your XML sitemaps does not matter – Google combines sitemaps and process them all at once.
Google ignores priority and change frequency tags in XML sitemaps
Submission of an XML sitemap does not replace normal crawling. Not submitting your XML sitemap does not stop Google from crawling your website.
There is no need to create separate sitemaps for your website and the AMP version
Security
If you moved your website to HTTPS but still get traffic to your HTTP web pages long after the migration, there might be some issues with your website. Check your redirects and canonicals.
SEO Content
You will not lose rankings for using informal (slang) language on your website.
Affiliate websites can still rank high in the search results if they are of high quality i.e. useful and relevant content, optimized for mobile-devices and secure.
Do not place the same content on multiple subdomains as this does not add value to users. If you have to do this then use canonical tags to tell Googlebot which is your preferred version or the master copy.
Use actual authors names than generic titles such as ‘Admin’ ‘User’. It helps Google establish the expertise, authority and trustworthiness of the author which influences how content ranks in the search results.
An embedded video should support your main content not replace it
Web pages that get low organic traffic doesn’t mean Google treats them as low quality.
Don’t worry too much of spammy websites stealing your content and re-writing it (spinning) as Google is clever at catching these websites out.
Do not worry about placing links to other websites in the first paragraph of your content. Google opens a page, parses the content and pulls out all the info from the page and then follows all the links found therefore all links regardless of position are equal.
H1-H5 heading tags on web pages help Google better understand the context of these pages.
Off-Page SEO
Be careful when syndicating content to websites with higher authority than your website. Doing so means your content could rank higher in search results for other websites than when it is on your website.
Robots.txt and Directives
Do not confuse the Googlebot with conflicting or incorrect directives
Canonicalization, Rel= Attributes
User the Google Inspection Tool (f in Google Search Console) If you want to see the canonical tag Google chose for a particular web page.
Use the Google Disavow tool (in Google Search Console) ONLY if your Backlink profile has many low-quality Backlinks that could potential trigger a Manual Action/Penalty from Google.
Google uses multiple factors to determine which page is canonical:
Rel=canonical
Redirects
Internal and external links
Sitemap
Hreflang link
Use self-referencing canonicals as best practice. Self-referencing canonicals help Google understand what URL is more important when people use URLs with parameters.
Local SEO
If your local business website is not found on Google My Business, it does not mean Google will not show your local business in the local organic search results.
Use consistent business contact information across the internet so as not to confuse Google one what business information to display in the search results
Speed
Google PageSpeed Insights score is based on Lighthouse data which measures for a 3G connection on a medium performance phone.
A high score on Web.dev tool does not lead to Google giving your website a ranking boost.
Speed is not the only critical ranking factor Google uses. Relevance is still important. That is why in some cases slow websites rank high in the search results.
Structured Markup
You can combine different types of schema markup on a single page.
Errors in one schema markup type don’t influence your other schema markups on your web pages. Google looks at different markup types ‘on a feature level’ which means that if a particular type of structured data is valid, it will be used in search results even if another type throws errors.
It’s better to have structured data directly added to a page rather than use Google Tag Manager to inject it as this method is prone to mistakes/errors.
Google prefers JSON-LD markup to microdata
The displayed date on your website blog post should be the same as the date in structured data for that post.
Use the Events structured data markup for actual real-world events (don’t use the markup for webinars or virtual events)
Google will no longer display self-hosted or 3rd party reviews in the search results.