Web Performance

Performance Metrics

• First Contentful Paint
• Speed Index
• Speed Index
• Time to Interactive
• First Meaningful Paint
• First CPU Idle
• Max Potential First Input Delay

Lighthouse

WebPageTest

• Load Time
• TTFB
• First Contentful Paint
• Start Render
• Speed Index
• Total Blocking Time
• Last Painted Hero

Page weight

TTFB

Start Render

Speed Index

Total Number of Requests

Perceived Performance 

 It’s a measure of how fast a user thinks your website is, not necessarily how fast your technical stats say it is

Guide

• Audit your page
• Use tools to find improvements
• Introduce changes one by one
• Audit after each change

Overall

Performance Tools are fine, they give you some hints but don't blindly trust them