Web Performance Analysis & Optimization tools

 If you cannot measure it, you cannot improve it - Lord Kelvin

There are a bunch of free Web Performance Analysis & Optimization tools that web developers can take advantage of to build blazing fast web pages -
These tools provide suggestions that not just cut page download time but also operational costs. I learnt about some of these tools from web performance guru Steve Souders' blog

Also see:
HOW TO improve the front-end performance of a website
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