JavaScript Performance

How to speed up your JavaScript code.

Reduce Activity in Loops

Each statement in a loop, including the for statement, is executed for each iteration of the loop.

Statements or assignments that can be placed outside the loop will make the loop run faster.

Reduce DOM Access

If you expect to access a DOM element several times, access it once, and use it as a local variable.

Reduce DOM Size

Keep the number of elements in the HTML DOM small,this will always improve page loading, and speed up rendering, especially on smaller devices.

Avoid Unnecessary Variables

Don’t create new variables if you don’t plan to save values.

JavaScript Functions

A JavaScript function is a block of code designed to perform a particular task, function is executed when “something” invokes it.

Why Functions?

You can reuse code: Define the code once, and use it many times.