title: Base64 conversion decimals
body: <p>I've been reading about base64 conversion, and what I understand is that the encoded version of the original data will be 133% of the original size.</p>
  
  <p>Then, I'm reading about how YouTube is able to have unique identifiers to their videos like <code>FJZQSHn7fc</code> and the reason was: an 11 character base64 string can map to a huge number.</p>
  
  <p>Wait, say a huge number contains 20 characters, then wouldn't a base64 encoded string be 133% of that size, not shorter?</p>
  
  <p>I'm very confused. Are there different types of base64 conversion (string to base64 vs. decimal to base64), once resulting in a bigger, and the other in a smaller resulting string?</p>