After surfing through hundreds of jsperf tests, today I bring to you jsperf – best of (2000-2013). For those who don’t know, is an online tool that provides us with JavaScript performance testing. Very useful for Improving your JavaScript & jQuery code performance / comparing the speed of different algorithms and code snippets! This post gives a super fast overview of the results of some of the best ones I’ve seen (so far).

There are quite a few tests so I’ve split them into the following Speed Test groups:

As always leave comments and if I’ve missed any you think are important please share. Let’s improve our coding and speed up the web!

jQuery Selector Speed Tests

These tests compare the performance of the different jQuery selectors.

id vs class vs tag vs pseudo vs. attribute selectors


Quick look at the speed of different jQuery selectors.


JavaScript String Speed Tests

Concatenating Literals

Comparing the speed of concatenating literals vs one long string assignment

String concatenation vs Regex


jQuery .size() vs .length.

Testing how much slower the jQuery method size() is against checking the length directly.

JavaScript DOM Caching/Traversal

DOM Caching vs No DOM Cache

Test the performance of DOM caching in a basic JavaScript namespacing pattern.

Caching DOM references outside of a loop


DOM caching excercise and node types


jQuery filter vs find.


Sam Deering is a Front-end Web Developer who specialises in JavaScript & jQuery. Sam is driven and passionate about sharing his knowledge to educate others.

Free Guide:

How to Choose the Right Charting Library for Your Application

How do you make sure that the charting library you choose has everything you need? Sign up to receive this detailed guide from FusionCharts, which explores all the factors you need to consider before making the decision.

Special Offer
Free course!

Git into it! Bonus course Introduction to Git is yours when you take up a free 14 day SitePoint Premium trial.