WebPerf and front-end quality testing tool
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Yellow Lab Tools

Analyzes a webpage and detects performance or front-end code quality issues. Free, easy to launch, easy to understand, in-depth details.

No website should go live without being tested with Yellow Lab Tools

The online tool (recommended): https://yellowlab.tools
The CLI (Command Line Interface) - Doc here
The Grunt task: gmetais/grunt-yellowlabtools
For developers or Continuous Integration
The NodeJS package - Doc here
The public API - Doc here
Allows you to launch runs from any language

How it works

The tool loads the given URL via PhantomJS (a headless browser) and collects various metrics and statistics with the help of Phantomas. These metrics are then categorized and transformed into scores. It also gives in-depth details so developpers can fix the detected issues.

By the way, it's free because we are geeks, not businessmen. All we want is a ★ on GitHub, it will boost our motivation to add more awesome features!!!

example dashboard screenshot

Test your localhost

You can use ngrok, a tool that creates a secure tunnel between your localhost and the online tool (or the public API). You can also use the CLI or the Grunt tasks as they run on your machine.

Install your own private instance

If your project is not accessible from outside, or if you want to fork and improve the tool, you can build your own instance. The documentation is here.


Gaël Métais. I'm a webperf freelance. Follow me on Twitter @gaelmetais, I tweet about Web Performances, Front-end and new versions of YellowLabTools!

I can also help your company about Web Performances, visit my website.