Exhaustive List of URL Shorteners

Go2.me started as a small hobby project, and has grown in scope as I've found many possible features to add.

There are a wide variety of Link Shorteners in the market today. The first products appeared in 2001, and people have used them to shorten 100's of millions of URL's to date. With the advent of micro-blogging sites, like Twitter, the demand for URL shorteners has grown even greater.

TinyURL is the first URL Shortener to gain wide popularity. Started in 2002 by Kevin "Gilby" Gilbertson, TinyURL remains the single most popular URL Shortening service, with a claimed 145 million links shortened to date, and 1.5 billion clicks per month (nearly 600 per second) on their shortened links (as of January, 2009).

There are a number of reasons why people are using URL Shorteners:

• Fixing Links - Original links may be too long to fit on a single line in an email message, causing some email clients to wrap them, making the link unusable.
• Beautifying Links -Original links are long and ugly - a shorter one looks better in email or IM messages.
• Space requirements - Twitter messages only allow 140 characters - long URL's won't fit, or don't allow enough explanatory text to accompany a shared link.
• Spam and Phishing - Spammers sometimes use URL Shorteners to disguise the true destination of a link. They can claim it will take a reader to one destination, when if fact it goes to another. This can make it more difficult for spam filters to recognize spam messages, and can also fool users into falling for a phishing scheme.
• Link Tracking - Individuals and marketers who are sharing links, often like to know how many people are clicking their link, or know what site people are clicking from.

TinyURL defined the baseline functionality by which we can judge follow on competitors. As an early entrant, the feature set is basic, with a couple advanced features.

• Redirection - Redirects from a short URL back to the original.
• Web Form - Type a link into a web form to shorten it.
• Custom Alias - Select your own text (if available) for a tiny link (e.g. http://tinyurl.com/blog-go2me.
• Bookmarklet - Install a bookmarklet to create a short URL from the current page.
• Relative Redirection - TinyURL links can be appended by additional URL path text to redirect to a "sub page" of the original shortned URL.
• Link Preview - Turn on preview mode (remembered by cookie) to display the target link BEFORE redirecting to it (used to confirm link is not spam, adult, or phishing).
• API - TinyURL supports a simple web request that will return the tiny URL from a long link - very simple but it works for many applications, for example Twhirl.

In a future post, I'll review the most popular (stand-alone) URL Shorteners (and throw in a comparison to the Go2.me service as well); sites that do URL shortening as an added feature (e.g., FriendFeed's "ff.im") will not be considered.

"Complete" List of URL Shorteners

The following list is EVERY URL shortener I have found to date (and I'll update it as I find more - if you know of additional shorteners, please send mail to shortener@go2.me). As a measure of their relative popularity, they are listed in order of their published Alexa Ranking (most as or Jan 2009, but some updated in Apr 2009). The sites that are highlighted will be the subject of my next post - a competitive review of the features of the most popular URL Shorteners.

Update 1: I've estimated the number of Tweets per Day that each service is being used to send. The front runners on the list are sorted by that statistic, rather than Alexa rank as it seems a purer measure of popularity.

Update 2: Twitter Rate numbers from May 2009 - also showing relative change in rank of each shortener from last statistics in April.

Update 3: Updated June 11, 2009. Note Stumble Upon's new shortener su.pr is already getting lots of mentions on twitter, even though it's still in limited beta.

The LAST Update: I'm going to post updated stats in a fresh blog posts from now on.

Thanks to Chris Koss for doing the competitive research for this post.