A "text rank" based client side JavaScript summarizer library. This a port of this python script to javascript. The "text rank" algorithm used in this library is well explained here. It is a naive summarizer algorithm and works fine in long well formatted and paragraphed texts.
<script type="text/javascript" src="js/summary.js"></script>var input = 'A major change that has occur.........';
var summary = get_summary(input);
console.log(summary);