title: URL Shortening: What's the best encoding to use?
body: <p>I'm adding a feature to my project where we are generating links to internal stuff of our website, and we want these links to be as short as possible, so we'll be making our own "URL Shortener".</p>
  
  <p>I'm wondering what's the best encoding / alphabet to use for the generated short URLs.
  This is largely a subjective question, I'd like to know what your opinions are regarding the best approach / trade-off.</p>
  
  <p>Several options I've thought of:<br>
  - Digits, uppercase + lowercase (base 62)<br>
  - Digits, only lowercase (base 36)<br>
  - Base 32 (<a href="http://www.crockford.com/wrmg/base32.html" rel="nofollow noreferrer">http://www.crockford.com/wrmg/base32.html</a>)<br>
  - linkpot.net (using common short english words)  </p>
  
  <p>Of course, the second two are better for uses other than clicking, and the first two are better for Twitter.</p>
  
  <p>Also, if I'm going with "clickable-only" URLs, I'd like to make the alphabet as large as possible, adding other symbols.</p>
  
  <ul>
  <li>What symbols can I use in URLs that won't get URL encoded?   </li>
  <li>What symbols <em>should</em> I use? Could some of these prove problematic? I'm thinking slash and dot, for example.  </li>
  </ul>
  
  <p>What do you think?</p>
  
  <p>NOTE: The main target for these URLs is Twitter. Keeping this in mind, we should probably have the largest alphabet possible, since most people will be clicking. However, I'm interested in your experience with people using short URLs in other ways (over the phone, in printed paper, etc). How likely is it this could happen?</p>
  
  <p>NOTE 2: I'm not making "yet another URL shortener", please don't condemn me with downvotes. We are generating short URLs for internal stuff in our site, not allowing anyone to shorten any URL. Imagine Google Maps giving you short URLs when you generate a link to a specific coordinate.</p>