Web Performance
Planted 02022-09-18
- MDN: What is web performance?
- WebPageTest: Lightning fast web performance
- web.dev: 2023 top Core Web Vitals recommendations
YSlow
Yahoo!โs Exceptional Performance team has identified 34 rules that affect web page performance. YSlowโs web page analysis is based on the 23 of these 34 rules that are testable.
- Minimize HTTP Requests
- Use a Content Delivery Network
- Avoid empty src or href
- Add an Expires or a Cache-Control Header
- Gzip Components
- Put StyleSheets at the Top
- Put Scripts at the Bottom
- Avoid CSS Expressions
- Make JavaScript and CSS External
- Reduce DNS Lookups
- Minify JavaScript and CSS
- Avoid Redirects
- Remove Duplicate Scripts
- Configure ETags
- Make AJAX Cacheable
- Use GET for AJAX Requests
- Reduce the Number of DOM Elements
- No 404s
- Reduce Cookie Size
- Use Cookie-Free Domains for Components
- Avoid Filters
- Do Not Scale Images in HTML
- Make favicon.ico Small and Cacheable