The rise of URL shortening

Anyone familiar with Twitter will no doubt have used URL shortening. URL shortening is a technique used to, as the name clearly suggests, shorten the number of characters required for a given URL/link. With Twitter’s 140 character limit, this has become an invaluable technique for adding links to tweets.

But URL shortening is also being used in places other than Twitter (and has been for a number of years). Many are using URL shortening to consolidate long URLs on Web sites, for external links in blog posts, links to downloadable content, and many other things. Some are using these shortening services to make long or complicated URLs easier to read and retype by users, and some for reducing the risk of malformed URLs being sent in emails, with longer and complicated URLs at risk from corruption by varying email clients’ interpretation and multi-line breakage.

Without doubt these services have great value – but their use should be done with caution.

Why caution?

URL shortening services utilize purposely obtained short domain names, such as bit.ly, tinyurl.com, even domains like the amazingly short http://u.nu/. These services allow users to utilize their site, and short domain name, to create short URLs dynamically that ‘redirect’ to the specified URL of the user. Below is a prime example of the format of a shortened URL.

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So when a user submits their URL, it is stored by the URL shortening service and paired with this dynamically shortened URL. A user accesses the shortened URL, and the shortening service redirects the user to the real URL it is paired with. Herein lies the first cautionary item.

Reliability of URL Shortening Services

This is, in my opinion, one of the most important reasons for cautionary use of shortened URLs. Your URLs are stored on someone else’s servers, in someone else’s database, as part of someone else’s domain. Until the user gets that all-important redirect and conversion to your URL, everything resides with the URL shortening service. What happens if the service holding one of your regular links goes out of business? Chances are the servers will be unavailable. If not taken on by someone else, all the data for this service will be lost, and thus the link between the shortened URL that was once paired with your real URL will be severed forever. This means every time someone hits your shortened URL, they’ll reach a dead end. Not your site/content.
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‘Well, whats the likelihood that will happen? Pretty slim you scare monger’…I hear you say. Well, considering articles like this one from Mashable.com, detail over 90+ URL shortening services, the above could be more likely then you think. For one, a lot of these URL shortening services will suffer the same issues as many social media tools that exist. How to monetize their services. No matter what the motivations or objectives are of these services, money makes the world go round. Meaning, if there isn’t enough revenue available to maintain services or upgrade to meet growing data demands both in hardware and software development, services will end. Servers will be re-purposed. Data will be lost. Then considering the 90+ services available, there is a fair amount of competition in this market trying to ‘share the pie’.

Add to that, if some of these services are being run more for the owners’ (likely Web developers) interest, as opposed to revenue, there is the possibility that when these developers get bored of working with the service, it could go offline without any real notice or concern. Zi.ma recently became a prime example of the volatility of these services, when it went under. Luckily, its data was salvaged by another service – Kl.am, but just goes to show the at-risk nature of services such as these.

This is not to say that URL shortening services have zero chance of longevity or adequate levels of financial support to maintain operations. bit.ly recently raised $2 million in investment funding, and tinyurl.com has a speculated worth of $46 million (figures from Tech Crunch). But caution is still a necessity as these are just two such services to have theorized resources to keep your links alive. Many others may not be so lucky. TinyURL also recently got dropped as the shortener of choice for Twitter, with the San Francisco-based startup opting for bit.ly instead. How much damage will this do to TinyURL? Does this put URLs shortened with TinyURL.com in jeopardy? Just one more example of the vulnerability that can exist with shortening services.

Further more in the realm of reliability – these services may suffer temporary downtime. With temporary downtime comes broken links, where users trying to reach your readily available content might be unable to do so because of outages on the side of the URL shortening service. With the user unable to use their deductive skills to find your domain from the short and unrelated URL, your link is lost until that service is once again available. Revenue can be heavily attributed to the reliability of such services. Those with less capital to meet the demands of a growing user base may find their hardware and software infrastructure unable to cope.

Whilst the above is a huge concern in URL shortening, it is not alone. As well as the reliability of URL shortening services, there are other factors that can contribute to why caution should be practiced when shortening URLs. Other factors to consider are detailed below.

URL Redirects

Without getting to complicated, URL redirects are the type of ‘redirect’ that occurs when the service moves from the shortened URL to the actual.

Services using a ‘301 redirect’ are saying to search engines that the content has been permanently moved from the shortened URL to your user-submitted original URL that its paired with. This means all the credit/’google juice’ for that link is given to the original user-submitted URL, exactly how it should be. When this occurs you get the credit for all the traffic coming to your originating content, links to your content and so on.

However, some services use non 301 redirects, such as ‘302 redirects’. This type of redirect tells search engines and other link crawling entities that the link has only ‘temporarily’ changed, and your originating URL is only the temporary location for the content accessed via the shortened URL. In turn, search engines, etc then attribute the shortened URL as being the primary URL for this content, and thus give the shortened URL all the credit. In this case all traffic, links, etc to your content would gain no SEO value, a very undesirable trait in almost any scenario.

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So it is thus vitally important to consider this when shortening your URLs. For those using URL shortening just in applications like Twitter, you may think that SEO value, etc does not impact what you are doing – but what if someone uses your shortened URL to send users to your site? Be it via a retweet in Twitter, or used in their blog citing your content, with a 302 redirect you would receive no credit for any of that traffic, and lets face it, you worked hard to create all that good stuff, you deserve the credit for it, right?

How Shortened URLs are Created

How some of these services deal with the shortening of user urls is another cautionary consideration when selecting, and using a service.

Without getting overly technical, these services use techniques to take the URL you supply, and create a character sequence to pair with it. That makes up your shortened URL. With short URLs being the goal, the fewer characters they use, the better.

However, the fewer characters there are, the fewer total combinations can exist. This means a finite number of unique URLs that that service can create for its users.

So the question is, what happens when the service runs out of URLs, and what do they do to combat such an issue? The first solution for these firms should be to increase the number of characters they use. Another solution – reuse/recycle already used, shortened URLs. Whilst the reusing of URLs by these services is unlikely, its not unfeasible. I don’t need to highlight the issue with a service overwriting a URL that you created. Whilst a service reusing URLs is highly unlikely, very few explicitly state that they would never use such a practice. This may not be a reason to discontinue using such services, but it does help further highlight why users should shorten URLs with caution, and consider best practices for when, and when not, to shorten (and with which service to do the shortening).

Raise Your Awareness

‘Being told to be cautious in your URL shortening activities, and being given details on where some pitfalls may lie is great, but how do I know whether any of this applies to the shortening service I use?’ you say. For more information on how these issues apply to the most commonly used URL shortening services, check out this absolutely fantastic URL Shorteners cross reference chart, created by Danny Sullivan of searchengineland.com. He has charted how the most pertinent features of URL shorteners apply to the top shortening services.

In his article Danny also considers what Twitter applications support which shortening services, an important consideration when factoring in that without advanced setup in many Twitter applications, the app itself will choose which URL shortener it will provide for your use. Also considered are a number of other advanced features not mentioned here.

Conclusion

The purpose of this post is not to devalue the usefulness and feasibility of URL shortening services. It is however purposed to make you aware that URL shortening should be done with caution, factoring in the appropriateness of the task for URL shortening, and the reliability of the service based on the numerous facets detailed above.

My overarching advice – only shorten when it’s necessary. Don’t shorten for the novelty of it, it adds an extra layer of potential risk that users will not be able to find your content. Avoid using in Web sites for any kind of navigation or page-to-page linking.

Use one of the services that does 301 redirects and use one of the more predominant services that has shown signs of financial validity and sustainable growth (eg bit.ly, tinyurl.com). That being said, with bit.ly becoming the shortener of choice for Twitter, and with the co-founders of Twitter having a financial stake in it, bit.ly could potentially be the safest bet of them all at this point.

Check your Twitter app to see what it defaults to for URL shortening, so you aren’t unknowingly using one of the ‘less reliable.’

Generally work with sense – ask yourself, if the link was to fail three months from now, would this cause critical issues for your business? Do you have a valid reason for shortening the URL?

If you are shortening URLs in your site simply because you hate the length, format or ugliness of your own current URLs, talk to us about our SEO admin system and how it can easily allow you to create more friendly URLs in your site with ease and full user control.

Use a URL shortening service all the time and worry about its reliability? Have experience with issues when using URL shortening services? Like to tell others your recommendation for reliable URL shortening services? Then please leave a comment on this post.