Link rot: what is it and how can I prevent it?

Everything, especially when not maintained or cared for properly, will decay with time. Some photographers are fascinated by this process and will visit abandoned building, to document them falling into ruin.

If a tree falls in a forest, microbes and insects will aid the decomposition process, helping recycle nutrients into the soil, out of this, new life can grow.

Using this analogy, the internet isn’t dissimilar to a forest and if you think of your digital assets as the forest’s flora then you can understand how over time, they will complete a life-cycle and stop working. However, decomposition in a “digital forest” is binary, and links will fail suddenly, without many signs of what might come.

When link profiles, or collections of links decay in a similar manner, we refer to this as link rot.

Link rot can happen to literally any hyperlink you create; whether that’s a clickable phone number link, email address or even a PDF – if one of the elements required for the link to work fails, the functionality is immediately compromised.

This process is completely normal and to be expected (and not always an unwelcome one), but it can degrade the user experience to the point where it’s value decreases, so it’s beneficial to be aware of it can attempt to control it.

Why does link rot happen?

Link decay will inevitably occur over time, but the rate at which it happens can differ greatly based on the nature of the link collection, and a variety of factors, such as a changes to internal linking structures, altered link destinations, hosting, domain name changes, and alterations to services terms and conditions which can further decrease the lifespan of online assets.

Link rot isn’t an SEO specific issue either and is experienced in programming and referred to as a “dangling pointer” – and occurs when a reference is to an object that no longer exists. On website this occurs when a link is pointing to a resource which has become unavailable –product page for a product that is no longer sold on an ecommerce site which hasn’t got a product retirement strategy, a blog post that has been removed during a content pruning exercise, or a whitepaper created by a think-tank that has been since dissolved.

How can we prevent link rot?

On an asset we can control the simple answer to link rot is redirection. This is the most common and best solution to link rot that you need to factor into any strategy that involves renaming, deleting, or the restructuring of a site. Various content management systems have extension that can aid this process.

However, when redirecting you also need to be very careful of content drift – this is what happens when on-page content shifts too much from the original content, making the reference no longer relevant to the destination of the link.

For example, if you a see a link to a website with pictures of cats, and the anchor text says: “cat photos”, people will expect to see cat pictures when they follow the link. But maybe over the years the page linked to has changed slightly, maybe the webmasters interest has shifted and now they post pictures of dogs rather than cats, but the anchor text references cats. One could conclude that the content has “drifted” away from cats to dogs.

Now in that example it’s innocuous, but sometimes content drift can be a real problem, at which point it may be better to simply remove the link to resources entirely. This is one example of where link rot can be a good thing as it allows the link to naturally drop off – in some cases it would be better for a link to fail that lead to a potentially irrelevant site.

Case Study

Million Dollar Homepage

The Million Dollar homepage is a self-certified piece of internet history and is one of the best examples of link rot. It was launched in August 2005 by university student called Alex Tew trying to make some extra money by dividing the visible portion of the site into a gid and selling 10×10 pixels, that offered a customisable link and a tooltip, and allowed the purchaser to upload an image the size of their purchased real estate. The site became a viral sensation and pixels were bought up by a range of different actors – from get-rich-quick schemes and dating sites to emerging artists and more established businesses like Orange and Yahoo.

The pixels sold out in 2006, but by 2017 it had stopped functioning as intended due to a degree of link rot.

Why is it important?

Over the years a few studies have been carried out on the subject of the Million Dollar Homepage to see how many links are still active, and most recently we conducted our own investigation.

We found that:

• 27% of the links resulted on a site loading with no redirects – with a portion of these leading to domain holding pages (“soft” link rot)
• 45% of links were redirected – many to sites which no longer reflect the nature of the original link – the became affected by intentional or unintentional content drift
• 28% returned various error messages – timeouts, DNS failures and 404 errors (“hard” link rot)

The site is still live today and almost feels like a time capsule from 2006, is a very interesting piece of internet history, and is a great example of how much the internet evolved.

Final thoughts

It’s a good idea to understand the extent that link rot is affecting your site, sites that link to you and sites you link to. This is so you can know what strategies might be useful to employ to compensate for it and stop the rot from limiting your growth, and compromising how useful the content on your site is.

Sometimes this process can be easier to accept if there is outdated content that hasn’t been maintained and eventually a domain or the hosting not being renewed and returning a Not Found error.

If you’re concerned about your link profile, degradation of your content or other effects of link rot make sure to reach out and we can put together a strategy to keep your site healthy, up-to-date, and useful to your visitors.