I wonder how well a shortener that included a clue about the domain would be. e.g. suppose that you shortened an amazon.com link to

http://amazon.XXX.YY/ABC

where XXX.YY is some suitable 6 letter domain name and ABC is a three letter hash. Assuming three letters from the valid [0-9A-Za-z] you have 62^3 possible links _per domain_. Extending to four characters you'd have 62^4 (over 14m links _per domain_).

So an amazon.com link would drop to 25 characters. A TinyURL link is currently 25 characters (bit.ly would be 18). So this is still in the ballpark.

Of course, the results aren't consistent (e.g. a ycombinator.com link would have 30 characters). But it would give a lot of information. Also, I think for non-.coms you'd have to include the TLD.

An advantage of using subdomains it that on YC/Reddit/Digg these links could easily be made to show as, for example, amazon.XXX.YY

You should probably consider truncating long domains. Maybe if it is > 7 characters, truncate to 7. Something like that. It would run the risk of collisions.

It may be worth also allowing users to suggest the shortening of the url the first time a domain is submitted. Just truncate ycominbator to yc etc.

I love this idea and if you decide not to pursue it, please let me know as this is something I would eagerly work on.

I am working on it.

If for some unexpected reason you need a hand, I'd be more than happy to help out. I'm pretty handy with php and I know I could throw together a better looking page than tinyurl.com.

I built it: http://twi.bz. It's very, very alpha. Email me with any problems.

That sounds like a really good idea actually. The only problem with this is that it would take more than the typical 10 lines of code (9 for interface) to set up a url shortener. Currently, all you need to set up a url shortener service is a domain name and a database.

It's about 11 lines of code. All you need to do add a wildcard entry in the DNS so that *.XXX.YY resolves to the same IP as XXX.YY, tell Apache to accept all Hostnames for that IP address, extract the subdomain from the hostname while extracting the hash.

I reckon I could get this up and running in about an hour if enough people upvote this comment :-)

I built it: http://twi.bz. It's very, very alpha. Email me with any problems.

Someone did it already: http://decenturl.com/

That doesn't do the same thing. It doesn't make short URLs, it makes shorter URLs that try to be readable.

You're right. I read your post before completely wake up.

I think it most amazing that Twitter has ubiquitized the short URL.

And, also, I agree.. URL shorteners suck. At least improve user experience by showing the original URL in the title attribute.

Ubiquitized within twitter.

You probably meant it that way but many people seem to forget over the hype how small twitter still is. Only 0.4% of internet-users have an account there and much less are actively using it.

Consequently short URLs being ubiquitous within twitter doesn't mean much in itself.

Perhaps we need a compacted URL standard? How about something MIME encoded, with a 5 bit prefix to handle the protocol, and Huffman coding for the rest? Then applications like Twitter and IM/MMS clients could simply decompress the URLs inline, and the whole thing would be transparent to the user.