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ender minyard
ender minyard

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The Ultimate Guide to Web Performance 🚀

There's so many ways to speed up your site. Don't you wish every web performance tip was in one place? That's what I thought too, so I put them all in one place: this post.

Use this guide as a reference.


Table Of Contents

HTML

Minify HTML
☄️ Order your styles and scripts for pagespeed
⚡️ Eliminate render-blocking resources
🌟 Minimize layout thrashing
🎉 Prioritize resources
Preload critical assets to improve loading speed
💥 Establish network connections early
⚡️ Prefetch resources
🌟 Implement adaptive serving

CSS

⭐️ Minify CSS
Remove unused CSS
💥 Defer non-critical CSS
⚡️ Minimize CSS requests by combining external CSS
🚀 Optimize CSS background images with media queries
⭐️ Avoid CSS inside the body tag
☄️ Inline critical CSS
Avoid expensive styles
💫 Optimize CSS length

Images

Choose the right image format
💫 Choose the correct level of compression
⭐️ Use Imagemin to compress images
💥 Defer offscreen images
⚡️ Properly size images
Replace animated gifs with video
🎉 Serve responsive images
⚡️ Serve images with correct dimensions
🌟 Use WebP images
⚡️ Use AVIF images
🎊 Use image CDNs to optimize images
Use lazy-loading
🚀 Lazy-loading video
⚡️ Use lazysizes to lazy-load images
⭐️ Compress JPEG images
🔥 Optimize PNG images
Optimize SVG vector files

Fonts

💫 Avoid invisible text during font loading
💥 Use preconnect to load fonts faster
⚡️ Optimize Webfont loading and rendering
☄️ Reduce Webfont Size
Keep Webfont size under 300kb

JavaScript

💫 Apply the PRPL pattern
⭐️ Limit the size of NPM dependencies
⚡️ Use code splitting
🌟 Combine external JavaScript
💥 Remove unused code
🎉 Use tree-shaking in Webpack
Minify JavaScript
💫 Serve modern code to modern browsers
🌟 See how CommonJS makes your bundles larger
⚡️ Defer loading JavaScript
⭐️ Prefer Vanilla JavaScript🎊
💡 Use service workers to cache data
🎊 Use web workers
💥 Write optimized code for V8
🎉 Compile your JavaScript to faster JavaScript with Prepack
Compile your JavaScript to faster JavaScript with Closure Compiler

Server

☀️ Use HTTPS
☄️ Keep the size of cookies low as possible
🔥 Avoid bad requests
💫 Set HTTP cache headers
⭐️ Enable gzip and brotli compression
⚡️ Self-host your static asssets
🌟 Enable OCSP stapling
💥 Adopt IPv6
💡 Serve assets over HTTP/2
🎉 Implement HPACK compression
Set proper security headers

Testing Tools

💫 Measure site speed with Pingdom
🌟 Measure site speed with WebPageTest
🎊 Measure performance with the RAIL model
⚡️ Configure Webpack performance hints
⭐️ Use bundlesize
💥 Measure JavaScript execution time
🎉 Use lighthouse-ci
☄️ Use Lighthouse Bot to set a performance budget
☀️ Test on remote real devices
🔥 Use Sitespeed
Use Calibre
💫 Use SpeedCurve
🎊 Use k6
⚡️ Use SpeedTracker

Frameworks

⭐️ Use an ahead of time compiler
💥 Improve Angular performance
☀️ Debug React perfomance
🔥 Eliminate common React issues
Make components connection aware
💫 Implement adaptive serving
🎉 Serve Adaptive Components Using the Network Information API




Did I miss something? Comment any potential additions to the list!

Top comments (37)

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dmahely profile image
Doaa Mahely

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machineno15 profile image
Tanvir Shaikh

This deserves a github repository .
like Awesome web performance..

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mketlinger profile image
Mike Etlinger

Nice! Lots of goodies in here and this is a great checklist.

The CSS section should have something like:

“Inline Your Critical CSS” which reduces the number of requests and helps with render blocking.

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ender_minyard profile image
ender minyard

Done!

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mketlinger profile image
Mike Etlinger

Nice thanks! I didn’t know about that Library.

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joelbonetr profile image
JoelBonetR 🥇

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z2lai profile image
z2lai

Just dope?

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joelbonetr profile image
JoelBonetR 🥇

What can I say, it's just what I needed to do that 😆

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z2lai profile image
z2lai

Yo that's dope.

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joelbonetr profile image
JoelBonetR 🥇

Just dope?

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sajeelhassan profile image
Sajeel Hassan

Recursion

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harrytheo profile image
Harry Theo

Amazing list you put there!! 🎉🎉 Thank you!

I have a few additions there you might want to include:

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miqueasgutierrez profile image
miqueasgutierrez

Hello, very good advice, it is also important to integrate Push Notifications in your website or online store for greater performance in the communication area, to carry out Ad campaigns, promotions, events, etc., I invite you to use the Indigital Service, you can carry out Marketing Campaigns Free for 30,000 devices, it is excellent and very easy to install, here is the Documentation: docs.indigitall.com/es/

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yogionbioinformatics profile image
Yogindra Raghav

THIS IS A GODSEND!!!!!!!!
How long did this take you to prepare?

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uploadcare profile image
Uploadcare

Impressive, thank you! We've also published a guide to responsive images and adaptive delivery technology, an easier way to serve responsive images: dev.to/uploadcare_/a-practical-gui...

Btw, if you're looking for a CDN for a media-heavy platform, here's a comparison of the 10 best solutions: bit.ly/3oYxr5E

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edwardinchains profile image
edwardinchains

content-visibility - limited browser support right now.

web.dev/content-visibility/

caniuse.com/css-content-visibility

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rahulh123 profile image
Rahul

How many of these amazing posts do you make? 😀 I guess I just got to go read all of them.

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ender_minyard profile image
ender minyard

:-) thanks!

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jurjin profile image
Giorgio Tempesta • Edited

I would add this one: Serve Modern Code to Modern Browsers for Faster Page Loads web.dev/serve-modern-code-to-moder...

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ender_minyard profile image
ender minyard

That's already in the article :-)

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jurjin profile image
Giorgio Tempesta

Sorry I completely missed it! 🙃

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rowemore profile image
Rowe Morehouse

You could add a critical-path sections, there may be some tools / techniques here for you to add to yours:

github.com/addyosmani/critical-pat...

:)

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ender_minyard profile image
ender minyard

The article already links to Addy Osmani's Critical library.

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juliomoreyra profile image
JulioMoreyra

Impressive list, very complete!

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qainsights profile image
NaveenKumar Namachivayam ⚡

Excellent list. Please add JMeter under testing tools.

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oscarrodar profile image
Oscar Rodriguez Arroyo

Nice!!! Thanks

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