JavaScript Reference
JS Reference is a free, complete guide to 1027+ JavaScript methods, functions, and properties. Every entry includes its syntax, parameter list, return value, a working code example, time complexity, and the TypeScript signature where applicable, covering everything from ES6 fundamentals to the latest ECMAScript APIs. Browse by category: Array, String, Number, Math, Date, Object, Map & Set, Promise, JSON, Console, DOM, RegExp, Global, Function, Symbol, Boolean, Error, Class, Proxy, Reflect, Typed Array, Iterator, WeakRef, Operators, Statements. Popular starting points include Array.prototype.map(), Array.prototype.filter(), Array.prototype.reduce(), Array.prototype.forEach(), Array.prototype.find(), Array.prototype.findIndex(), Array.prototype.findLast(), Array.prototype.some(), Array.prototype.every(), Array.prototype.includes(), Array.prototype.indexOf(), Array.prototype.push(), Array.prototype.pop(), Array.prototype.shift(), Array.prototype.unshift(), Array.prototype.slice(), Array.prototype.splice(), Array.prototype.concat(), Array.prototype.join(), Array.prototype.sort(). If you are learning the language, the 145 in-depth guides walk through entire topics step by step. For quick copy-paste utilities, the snippet library collects reusable patterns such as debounce and deep clone. The glossary defines key JavaScript terminology in plain language, and the ES version pages track what each ECMAScript edition added to the language. Use the search page to jump straight to any method, the A–Z index to browse everything, the playground to run code in your browser, or the blog for deep dives into how JavaScript really works.