When Will URL Shorteners Run Out of Links?

More than 250 million messages are tweeted daily. Approximately 290,000 status updates are posted to Facebook every minute. And who knows the number of instant messages that contain hyperlinks. Probably a lot.

One thing is for certain: A good number of those hyperlinks aren't in their original form. Thanks to URL shortening services, such as lnk.co and TinyURL, what's normally 56 characters in length for a YouTube clip can be cut down to 20, omitting all kinds of URL clutter from your Gchat message boxes and leaving plenty more room for commentary in your tweets.

But with all this link-sharing activity happening at lightning-fast rates and on ever-expanding platforms, how is it possible for these URL shortening services to keep up?

Considering most of these services say their links never expire (and, thus, cannot be recycled), they're bound to run out of character suffix combinations, right? Are URL shorteners soon to become less shortened? What's going to happen? Do aliens exist on earth? Did I forget to take my meds again?

The brainiacs behind the URL shrinking machine bitly were kind enough to answer the first question in that series. Even with 100 million shortened links saved per day and, so far, over 25 billion bitly links created since the company's 2008 inception, they don't seem to be sweating the issue:

"Bitly uses a six-character hash. Since they are alpha-numeric, each character in the hash can be A through Z, a through z, or 0 through 9. In total, there are 62 different character possibilities (26 for lower case alphabet, 26 for uppercase alphabet, and 10 for numbers). The total number of possible bitly links is thus 62 to the 6th power, which is 56,800,235,584." * "If we ran out of hash space, which we hope happens (it means we're super popular), we would simply add an additional letter to the hash. Seven letters would result in a hash space of 62 to the 7th power: 3,521,614,606,208!"

Tweetburner, a smaller shortening service based in the Netherlands, sees roughly seven percent of their links get broken within 500 days. So they have the possibility to re-use them, but there's a bigger reason they won't max out on link combinations. "If you look at Twitter, they also shorten other shortened URLs," says Tweetburner's Maurice Beckand Verwee. "I think they together with Facebook have the biggest challenge to keep up with the shortened links."