Blaze through the most common HTML entities without giving them a second thought. The syntax is simple: a colon : followed by the first character or two of the entity name.
Install via Sublime Text Package Control.
Create any fraction entity by altering the last two digits of ½. The last two digits are a snippet placeholder, you can quickly tab-edit the numbers.
fractions example
Using :12 yields ½ which is ½ . If you then change it to ¼ it will yield ¼ .