Web Performance Handbook#
Welcome to the web performance handbook! If you're here for a specific issue, try looking in the contents to the left or using your browser search function. If you're here to read, I suggest starting at the top.
Understanding web performance#
What is web performance?#
Why does it matter?#
What impacts web performance?#
How does it impact users?#
Measuring web performance#
What to measure#
Performance APIs#
Visual metrics#
Sizes#
Using your browser#
Device emulation#
Performance Profile#
Network tab#
Using free online tools#
PageSpeed Insights#
WebPageTest.org#
YellowLab.Tools#
Synthetic monitoring#
Real user monitoring#
Measure where it matters: Real vs Robots#
Measure what matters: Custom Timings#
Make it stick: Performance budgets#
Improving Site Speed#
Have a plan#
Critical path#
DNS#
TLS#
CDN#
Server Response#
HTML#
CSS#
JavaScript#
Images#
Third-party Content#
Single-Page Applications#
Prioritising important elements#
Identifying important elements#
importance attribute#
Preloading assets#
Loading attribute#
Adapting to the user#
save-data header#
#
Measure changes#
Celebrate success#
FAQs#
- Will product / tool / service / plugin make my site faster? Maybe, but is it something you could do yourself? Only exceptions are AMP, FIA etc.