Addy Osmani's 18-Point Web Performance Checklist

Ben Halpern on November 16, 2018

I was just perusing Addy Osmani's Ask Me Anything from this summer. While the post is full of wisdom, this comment stands out as web dev gold: ... [Read Full]
markdown guide

Some additional things to not do...

  • Don't include 20 different user tracking scripts.
  • Don't ignore performance.
  • Don't use the default web server configurations.
  • Don't use video backgrounds.
  • Don't load the page and then make a dozen ajax calls for content.
  • Don't use assets from third parties.
  • Don't rely on cookies.
  • Don't try to figure out my location.
  • Don't try to track every mouse click, scroll or movement.
  • Don't have long timeouts.
  • Don't cheap on hosting.
  • Don't forget to test usability under load.
  • Don't forget to test usability across multiple browsers/os.
  • Don't forget to enable TLS.
  • Don't include 20 different user tracking scripts.

"* Don't use video backgrounds"

Pretty please with sugar on top! Video breakthroughs may sound like a good idea, but in reality you're just learning how someone likes solve one specific problem. You're not really learning programming, or something even more important: problem solving.


But I love video backgrounds! That got me started with dev lol as I started off as a video artist. But yeah I agree the compression never usually does the quality justice and it is usually more trouble loading than fun


ðŸ“ē Respect data plans

So true – is a great resource to make you feel guilty about this one :)


My absolute #1 that everyone always seems to miss room these lists: minimise DOM complexity. This is the single most performance thing that users will notice once the content loads client side. The simpler the DOM, the quicker CSS rules can be applied and JavaScript selectors can search for the right nodes. Fast initial load times are worthless, if the site kills the CPU when trying to make any changes at all to the dynamic content.


Very useful we added to our checklist for making Gitote great!


A lot of these items could be addressed with minimal effort and complexity via server side rendering.


Meanwhile on the "real internet" I keep finding these

The biggest issue on the web are the images not JS and CSS, you should focus on the biggest ROI.

code of conduct - report abuse