Using the Word Count on Microsoft Word, it came out to 87 characters excluding the http://www.

No numbers have been published by the search engines so you have to use some common sense to figure this out. Domain names can be 63 characters long so it is safe to assume a URL may be that long.

I've seen some pretty lengthy URLs, thanks to query strings, in the SERPs of all of the major search engines. If I was going to offer a guess I would say 255 characters.

I am one who puts a LOT more weight on user usability than SEO. If you tailor every single aspect of your site with the user in mind, SEO just sorta falls into place. After all, the search engines are actually tailored to best perform on sites tailored for users That's why black hat SEO just isn't doing as well as it used to.

So very well said. If only we could get every webmaster to subscribe to this line of thinking.

It does not seem to affect rankings....... I have urls that count to over 90 characters..... But make sure you doesn't spam your url with no. of keywords.....

I also have several urls that long, the problem actually lies not on Search Engines, but the users... especially does who don't bookmark but memorize (yes there are this kind of users.)