Mathjs
An extensive math library for JavaScript and Node.js
Xdate
A Modern JavaScript Date Library
Auto Numeric
autoNumeric is a jQuery plugin that automatically formats currency (money) and numbers as you type on form inputs. It supports most International numeric formats and currency signs including those used in Europe, North and South America, Asia and India (lakhs**).
jQuery Number
Easily format numbers for display use. Replace numbers inline in a document, or return a formatted number for other uses.
Big.js
A small, fast JavaScript library for arbitrary-precision decimal arithmetic.
Sprintf.js
sprintf.js is a complete open source JavaScript sprintf implementation.
Date
Date() for humans
Tiny Color
Fast, small color manipulation and conversion for JavaScript
Inversify Js
A powerful and lightweight inversion of control container for JavaScript & Node.js apps powered by TypeScript.
Ratio.js
Rational numbers for Javascript
Char Funk
a Unicode character utility for JavaScript
Timezone Js
Timezone-enabled JavaScript Date object. Uses Olson zoneinfo files for timezone data.
Core Lib
A port of the Ruby 1.9.3 corelib to coffeescript/javascript/node that conforms to rubyspec.org.
Moment
Parse, validate, manipulate, and display dates in javascript.
Classing Js
Brings the world of classical OOP to javascript
Object.observe
Object.observe polyfill/shim trying to be compliant
Extract Values
A simple helper to extract values from a string based on a pattern.