Internal links are simply links which point from one page to another within the same domain.
These are vital for users to navigate a site, but they are often overlooked in terms of SEO.
They enable search engines to find your content, and you can’t be found in search results without that!
Although you can submit sitemaps and ping search engines when new content is published, the main method is for crawlers to hit your homepage and then crawl from there.
Most websites are set up so that if you create a page (blog post, product, etc.) then it will be added to your blog roll, product category, sitemap or somewhere else on your site. If you create a page and there are no links to it, then it simply won’t be found by crawlers.
These pages which can’t be found are orphaned pages. You may well have created some intentionally for PPC landing pages, email campaigns and other “hidden” resources – but in general you want your URLs to be found!
Much like external links, internal links can be seen as “votes” for a page, passing on equity from one page to another. This is on a lesser scale than external linking, but it very much defines how your site hierarchy is formed. Combined with your folder structure and hierarchy, the internal linking structure helps crawlers understand which pages are associated with each other.
If you regard a page highly then it should have a lot of links pointing to it. The opposite is true as well – if you don’t need to promote a page, it can be deeper in your site with less internal links.
There is also the matter of what the link anchor text is, and it has been confirmed that this is taken into account.
For menu linking and most categorization this will be done naturally, but this can become an issue with image links and links within content.
Images and banners with links in would ideally be coded in HTML so the text can be read properly. If this can’t be done, then you can apply alt tags and text to the links on images to help give context.
Links in content (sometimes called contextual links) are more straight forward. Like writing blogs and building links, you can link when you use the keyword anchor text, but make sure you aren’t being spammy and write for the user first.
Looking at a piece of example text from our homepage, here are examples of good and bad contextual internal linking.
“Specialising in search engine optimisation (SEO), content marketing, digital PR and paid search and social, we’re here to help…”
“Specialising in search engine optimisation (SEO), content marketing in Southampton, digital PR and paid search and social, we’re here to help…”
The bad example is indicative of link building methods from pre-Penguin days and doesn’t make sense to the user.
Above we mentioned the user a few times, and good SEO should always take this into account.
In terms of internal linking, the main points are context and relevancy. If your content talks about a certain product or service, then you can link to it when mentioned.
Think of these like information CTAs, giving the user opportunity to find out more easily and quickly. This helps users remain informed and can help push to conversion. Sometimes this may mean linking externally, but in this case you can set the link to open a new tab so that they aren’t navigating fully away from your site.
We know not all links are equal, but there are a few points you need to watch out for when working on internal linking on your site.
There are numerous ways to block pages with robots.txt files, meta headers, canonicals, etc. If you are pointing internal links to pages which are blocked, then these could be disregarded completely or have reduced impact.
An inevitable fact on any site, redirects can keep the user journey working, but they are an extra step for crawlers. Making sure your links are coded correctly and avoid redirects can help with speed, crawl budgets and generally keep your site healthy. This can seem like busy work, but if you spend hours cleaning up your external link profile, why shouldn’t you fix what you have control of?
Users can often interact with different site components to get to different areas. This can be from drop down boxes, different filters or through custom search features. Some of these will require a submit action, which crawlers don’t do – so they won’t get crawled!
If your category filters or other functions are active and load the page on the click rather than a submit/confirmation, then they will most likely be crawled. If you are reliant too much on your users narrowing searches down with these ‘submit’ style actions, then you could be heavily reducing your internal linking possibilities.
A thoroughly outdated practice, but it can still be seen from time to time. Don’t create links which are hidden offscreen to users. This can occasionally come into play with improperly coded responsive sites, but it is rare.
Too much can be a bad thing for many aspects of SEO. While too many links on a page isn’t strictly bad, it can be unnecessary. Crawlers work top to bottom and will stop after a few hundred internal links on one page.
You should also just link a reasonable amount, rather than every single mention, such as in well cited articles. If you are talking about “SEO Services”, then you will probably mention it a few times in the content, but you only need to link the first time, not every time.
The precise amount is vague and depends on numerous factors, but the rough crawl limit for links on a page is 150. Some pages will get crawled further, but it’s wise to get your important links higher up or your work risks being ignored.
I-frames are often a nightmare for SEO, but they are still frequently used – for third-party services and plugins in particular. Whilst links in I-frames can theoretically be crawled, they are also technically on different URLs to the rest of the page. It is best to keep your important internal linking within the crawler-friendly HTML rather than I-frames.
Linked to some of the other factors above, building sites with plugins can save time and money, but they often have unwanted side effects. One of these is that they can incorporate I-frames, unknown scripts, and third-party code which can affect if links are crawlable. There are too many cases to mention here, but if you are looking for some of the points above, they can often be traced back to plug-ins.
It might look like a lot to keep on top of, but the bulk of the points above are easily managed and once done will require only minimal upkeep.
As with many aspects of SEO, the focus is on crawlability and usability of your site. If it feels wrong or frustrating from a user perspective, then the search engine crawlers probably aren’t having a good time either!
The hardest part can be identifying the work to be done rather than carrying it out, so if you need help with your internal linking or general SEO, get in touch with us today.