Uh oh!
There was an error while loading.Please reload this page.
- Notifications
You must be signed in to change notification settings - Fork6.6k
🗂 The perfect Front-End Checklist for modern websites and meticulous developers
License
thedaviddias/Front-End-Checklist
Folders and files
| Name | Name | Last commit message | Last commit date | |
|---|---|---|---|---|
Repository files navigation
The Front-End Checklist is an exhaustive list of all elements you need to have / to test before launching your website /HTML page to production.
Other Checklists:
Tip
⭐️ Dev-friendly UX patterns you wish you knew. 👉UX Patterns for Devs ⭐️
Important
Disclaimer: This checklist is based on Front-End developers' years of experience, with additions from other open-source checklists.
All items in theFront-End Checklist are required for the majority of the projects, but some elements can be omittedor are not essential (in the case of an administration web app, you may not need RSS feed for example). We choose to use3 levels of flexibility:
indicates that the item is recommended but can be omitted in certain situations.
indicates that the item is highly recommended but can potentially be omitted in very specificcases. However, omitting these elements can negatively impact performance or SEO.
indicates that the item cannot be omitted under any circumstances. Removing these elements mayresult in page malfunctions or cause accessibility and SEO issues. Testing should prioritize these elements first.
Some resources possess an emoticon to help you understand which type of content / help you may find on the checklist:
- 📖: documentation or article
- 🛠: online tool / testing tool
- 📹: media or video content
Note
You can finda list of everything that could be found in the<head> of an HTML document.
- Doctype: The Doctype is HTML5 and is at the top of all your HTML pages.
<!doctype html><!-- HTML5 -->
The next 2 meta tags (Charset and Viewport) need to come first in the head.
- Charset: The charset (UTF-8) is declared correctly.
<!-- Set character encoding for the document --><metacharset="utf-8">
- Viewport: The viewport is declared correctly.
<!-- Viewport for responsive web design --><metaname="viewport"content="width=device-width, initial-scale=1, viewport-fit=cover">
- Title: A title is used on all pages (SEO: Google calculates the pixel width of the characters used in the title, and it cuts off between 472 and 482 pixels. The average character limit would be around 55-characters).
<!-- Document Title --><title>Page Title less than 55 characters</title>
Description:
A meta description is provided, it is unique and doesn't possess more than 150characters.
<!-- Meta Description --><metaname="description"content="Description of the page less than 150 characters">
Favicons:
Each favicon has been created and displays correctly. If you have only afavicon.ico, put it at the root of your site. Normally you won't need to use any markup. However, it's stillgood practice to link to it using the example below. Today,PNG format is recommended over.icoformat(dimensions: 32x32px).
<!-- Standard favicon --><linkrel="icon"type="image/x-icon"href="https://example.com/favicon.ico"><!-- Recommended favicon format --><linkrel="icon"type="image/png"href="https://example.com/favicon.png"><!-- Recommended modern favicon format (not recommended for legacy browsers) --><linkrel="icon"type="image/svg+xml"href="https://example.com/favicon.svg">
📖Favicons, Touch Icons, Tile Icons, etc. Which Do You Need? - CSS Tricks
Apple Web App Meta:
Apple meta-tags are present.
<!-- Apple Touch Icon (at least 200x200px) --><linkrel="apple-touch-icon"href="/custom-icon.png"><!-- To run the web application in full-screen --><metaname="apple-mobile-web-app-capable"content="yes"><!-- Status Bar Style (see Supported Meta Tags below for available values) --><!-- Has no effect unless you have the previous meta tag --><metaname="apple-mobile-web-app-status-bar-style"content="black">
Windows Tiles:
Windows tiles are present and linked.
<!-- Microsoft Tiles --><metaname="msapplication-config"content="browserconfig.xml">
Minimum required xml markup for thebrowserconfig.xml file is as follows:
<?xml version="1.0" encoding="utf-8"?><browserconfig> <msapplication> <tile> <square70x70logosrc="small.png"/> <square150x150logosrc="medium.png"/> <wide310x150logosrc="wide.png"/> <square310x310logosrc="large.png"/> </tile> </msapplication></browserconfig>
- Canonical: Use
rel="canonical"to avoid duplicate content.
<!-- Helps prevent duplicate content issues --><linkrel="canonical"href="http://example.com/2017/09/a-new-article-to-read.html">
- 📖Use canonical URLs - Search Console Help - Google Support
- 📖5 common mistakes with rel=canonical - Google Webmaster Blog
- Language attribute: The
langattribute of your website is specified and related to thelanguage of the current page.
<htmllang="en"></html>
- Direction attribute: The direction of lecture is specified on the html tag (It can beused on another HTML tag).
<htmldir="rtl"><!-- ... --></html>
Alternate language:
The language tag of your website is specified and related to the languageof the current page.
<linkrel="alternate"href="https://es.example.com/"hreflang="es">
- x-default: The language tag of your website for international landing pages.
<linkrel="alternate"href="https://example.com/"hreflang="x-default"/>
Conditional comments:
Conditional comments are present for IE if needed.📖About conditional comments (Internet Explorer) - MSDN - Microsoft
RSS feed:
If your project is a blog or has articles, an RSS link was provided.CSS Critical:
The CSS critical (or "above the fold") collects all the CSS used to renderthe visible portion of the page. It is embedded before your principal CSS call and between<style></style>in asingle line (minified).🛠Critical by Addy Osmani on GitHub automates this.
CSS order:
All CSS files are loaded before any JavaScript files in the<head>. (Except thecase where sometimes JS files are loaded asynchronously on top of your page).
Visualize and generate automatically our social meta tags withMeta Tags
Facebook OG andTwitter Cards are, for any website, highly recommended. The other social media tags can beconsidered if you target a particular presence on those and want to ensure the display.
- Facebook Open Graph: All Facebook Open Graph (OG) are tested and no one is missing or withfalse information. Images need to be at least 600 x 315 pixels, although 1200 x 630 pixels is recommended.
Note
Usingog:image:width andog:image:height will specify the image dimensions to the crawler so that it can render the image immediately without having to asynchronously download and process it.
<metaproperty="og:type"content="website"><metaproperty="og:url"content="https://example.com/page.html"><metaproperty="og:title"content="Content Title"><metaproperty="og:image"content="https://example.com/image.jpg"><metaproperty="og:description"content="Description Here"/><metaproperty="og:site_name"content="Site Name"><metaproperty="og:locale"content="en_US"><!-- Next tags are optional but recommended --><metaproperty="og:image:width"content="1200"><metaproperty="og:image:height"content="630">
🛠 Test your page with theFacebook OG testing
Twitter Card:
<metaname="twitter:card"content="summary"><metaname="twitter:site"content="@site_account"><metaname="twitter:creator"content="@individual_account"><metaname="twitter:url"content="https://example.com/page.html"><metaname="twitter:title"content="Content Title"><metaname="twitter:description"content="Content description less than 200 characters"><metaname="twitter:image"content="https://example.com/image.jpg">
- 📖Getting started with cards — Twitter Developers
- 🛠 Test your page with theTwitter card validator
HTML5 Semantic Elements:
HTML5 Semantic Elements are used appropriately (header, section,footer, main...).Error pages:
Error 404 page and 5xx exist. Remember that the 5xx error pages need to havetheir CSS integrated (no external call on the current server).Noopener:
In case you are using external links withtarget="_blank", your link shouldhave arel="noopener"attribute to prevent tab nabbing. If you need to support older versions of Firefox, userel="noopener noreferrer".Clean up comments:
Unnecessary code needs to be removed before sending the page to production.
W3C compliant:
All pages need to be tested with the W3C validator to identify possibleissues in the HTML code.HTML Lint:
I use tools to help me analyze any issues I could have on my HTML code.Link checker:
There are no broken links in my page, verify that you don't have any 404error.Adblockers test:
Your website shows your content correctly with adblockers enabled (Youcan provide a message encouraging people to disable their adblocker).
Note
Using web fonts may cause Flash Of Unstyled Text/Flash Of Invisible Text - consider having fallback fontsand/or utilizing web font loaders to control behavior.
Webfont format:
WOFF, WOFF2 and TTF are supported by all modern browsers.Webfont size:
Webfont sizes don't exceed 2 MB (all variants included).Webfont loader:
Control loading behavior with a webfont loader
Notes: Take a look atCSS guidelines andSass Guidelinesfollowed by most Front-End developers. If you have a doubt about CSS properties, you can visitCSS Reference. There is also a shortCode Guide for consistency.
Responsive Web Design:
The website is using responsive web design.CSS Print:
A print stylesheet is provided and is correct on each page.Preprocessors:
Your project is using a CSS preprocessor (e.gSass,Less,Stylus).Unique ID:
If IDs are used, they are unique to a page.Reset CSS:
A CSS reset (reset, normalize or reboot) is used and up to date.(If you areusing a CSS Framework like Bootstrap or Foundation, a Normalize is already included into it.)JS prefix:
All classes (or id- used in JavaScript files) begin withjs- and are not styledinto the CSS files.
<divid="js-slider"class="my-slider"><!-- Or --><divid="id-used-by-cms"class="js-slider my-slider"></div></div>
embedded or inline CSS:
Avoid at all cost embedding CSS in<style>tags or using inlineCSS: only use for valid reasons (e.g. background-image for slider, critical CSS).Vendor prefixes:
CSS vendor prefixes are used and are generated accordingly with yourbrowser support compatibility.
Concatenation:
CSS files are concatenated in a single file(Not for HTTP/2).Minification:
All CSS files are minified.Non-blocking:
CSS files need to be non-blocking to prevent the DOM from taking time toload.Unused CSS:
Remove unused CSS.
Stylelint:
All CSS or SCSS files are without any errors.Responsive web design:
All pages were tested at the following breakpoints: 320px, 768px,1024px (can be more / different according to your analytics).Responsive Checker -CSS Validator:
The CSS was tested and pertinent errors were corrected.Desktop Browsers:
All pages were tested on all current desktop browsers (Safari, Firefox,Chrome, Internet Explorer, EDGE...).Mobile Browsers:
All pages were tested on all current mobile browsers (Native browser,Chrome, Safari...).OS:
All pages were tested on all current OS (Windows, Android, iOS, Mac...).Design fidelity:
Depending on the project and the quality of the creatives, you may be askedto be close to the design. You can use some tools to compare creatives with your code implementation and ensureconsistency.
Reading direction:
All pages need to be tested for LTR and RTL languages if they need to besupported.📖Building RTL-Aware Web Apps & Websites: Part 1 - Mozilla Hacks
📖Building RTL-Aware Web Apps & Websites: Part 2 - Mozilla Hacks
Notes: For a complete understanding of image optimization, check the free ebookEssential Image Optimization from Addy Osmani.
Optimization:
All images are optimized to be rendered in the browser. WebP format could beused for critical pages (like Homepage).🛠 UseImageOptim to optimise your images for free.
🛠 UseKeyCDN Image Processing for image optimization in real time.
🛠TinyPNG optimises png, apng (animated png) and jpg images with very small loss in quality.Free and paid version available.
🛠ZorroSVG jpg-like compression for transparent images using svg masking.
🛠SVGO a Nodejs-based tool for optimizing SVG vector graphics files.
🛠SVGOMG a web-based GUI version of SVGO for optimising your svgs online.
Picture/Srcset:
You use picture/srcset to provide the most appropriate image for thecurrent viewport of the user.Retina:
You provide layout images 2x or 3x, support retina display.Sprite:
Small images are in a sprite file (in the case of icons, they can be in an SVGsprite image).Width and Height:
Setwidthandheightattributes on<img>if the final rendered imagesize is known (can be omitted for CSS sizing).Alternative text:
All<img>have an alternative text which describes the image visually.Lazy loading:
Images are lazyloaded (A noscript fallback is always provided).
JavaScript Inline:
You don't have any JavaScript code inline (mixed with your HTML code).Concatenation:
JavaScript files are concatenated.Minification:
JavaScript files are minified (you can add the.minsuffix).JavaScript security:
📖Guidelines for Developing Secure Applications Utilizing JavaScript
noscripttag: Use<noscript>tag in the HTML body if a script type on the page isunsupported or if scripting is currently turned off in the browser. This will be helpful in client-side renderingheavy apps such as React.js, seeexamples.
<noscript> You need to enable JavaScript to run this app.</noscript>
Non-blocking:
JavaScript files are loaded asynchronously usingasyncor deferred usingdeferattribute.Optimized and updated JS libraries:
All JavaScript libraries used in your project arenecessary (prefer Vanilla Javascript for simple functionalities), updated to their latest version and don'toverwhelm your JavaScript with unnecessary methods.Modernizr:
If you need to target some specific features you can use a custom Modernizr to addclasses in your<html>tag.
ESLint:
No errors are flagged by ESLint (based on your configuration or standards rules).📖ESLint - The pluggable linting utility for JavaScript and JSX
HTTPS:
HTTPS is used on every page and for all external content (plugins, images...).HTTP Strict Transport Security (HSTS):
The HTTP header is set to'Strict-Transport-Security'.Cross Site Request Forgery (CSRF):
You ensure that requests made to your server-side arelegitimate and originate from your website / app to prevent CSRF attacks.📖Cross-Site Request Forgery (CSRF) Prevention Cheat Sheet - OWASP
Cross Site Scripting (XSS):
Your page or website is free from XSS possible issues.Content Type Options:
Prevents Google Chrome and Internet Explorer from trying tomime-sniff the content-type of a response away from the one being declared by the server.X-Frame-Options (XFO):
Protects your visitors against clickjacking attacks.Content Security Policy:
Defines how content is loaded on your site and from where it ispermitted to be loaded. Can also be used to protect against clickjacking attacks.
Goals to achieve:
Your pages should reach these goals:- First Meaningful Paint under 1 second
- Time To Interactive under 5 seconds for the "average" configuration (a $200 Android on a slow 3G network with 400msRTT and 400kbps transfer speed) and under 2 seconds for repeat visits
- Critical file size under 170Kb gzipped
Minified HTML:
Your HTML is minified.Lazy loading:
Images, scripts and CSS need to be lazy loaded to improve the responsetime of the current page (See details in their respective sections).Cookie size:
If you are using cookies be sure each cookie doesn't exceed 4096 bytes andyour domain name doesn't have more than 20 cookies.Third party components:
Third party iframes or components relying on external JS (likesharing buttons) are replaced by static components when possible, thus limiting calls to external APIs and keepingyour user's activity private.
DNS resolution:
DNS of third-party services that may be needed are resolved in advance duringidle time usingdns-prefetch.
<linkrel="dns-prefetch"href="https://example.com"/>
- Preconnection: DNS lookup, TCP handshake and TLS negotiation with services that will be neededsoon is done in advance during idle time using
preconnect.
<linkrel="preconnect"href="https://example.com"/>
- Prefetching: Resources that will be needed soon (e.g. lazy loaded images) are requested inadvance during idle time using
prefetch.
<linkrel="prefetch"href="image.png"/>
- Preloading: Resources needed in the current page (e.g. scripts placed at the end of
<body>)in advance usingpreload.
<linkrel="preload"href="app.js"/>
Google PageSpeed:
All your pages were tested (not only the homepage) and have a score of atleast 90/100.
Notes: You can watch the playlistA11ycasts with Rob Dodson 📹
Progressive enhancement:
Major functionality like main navigation and search should workwithout JavaScript enabled.Color contrast:
Color contrast should at least pass WCAG AA (AAA for mobile).
H1:
All pages have an H1 which is not the title of the website.Headings:
Headings should be used properly and in the right order (H1 to H6).📹Why headings and landmarks are so important -- A11ycasts #18
Specific HTML5 input types are used:
This is especially important for mobile devicesthat show customized keypads and widgets for different types.
Label:
A label is associated with each input form element. In case a label can't bedisplayed, usearia-labelinstead.
Accessibility standards testing:
Use the WAVE tool to test if your page respects theaccessibility standards.Keyboard navigation:
Test your website using only your keyboard in a previsible order. Allinteractive elements are reachable and usable.Screen-reader:
All pages were tested in a screen-reader (VoiceOver, ChromeVox, NVDA orLynx).Focus style:
If the focus is disabled, it is replaced by visible state in CSS.
Google Analytics:
Google Analytics is installed and correctly configured.Search Console:
Search Console is installed and correctly configured. It is a free serviceoffered by Google that helps you monitor, maintain, and troubleshoot your site's presence in Google Searchresults.Headings logic:
Heading text helps to understand the content in the current page.sitemap.xml:
A sitemap.xml exists and was submitted to Google Search Console (previouslyGoogle Webmaster Tools).robots.txt:
The robots.txt is not blocking webpages.🛠 Test your robots.txt withGoogle Robots Testing Tool
Structured Data:
Pages using structured data are tested and are without errors. Structureddata helps crawlers understand the content in the current page.📖Introduction to Structured Data - Search - Google Developers
🛠 Test your page with theRich Results Test
🛠 Complete list of vocabularies that can be used as structured data.Schema.org Full Hierarchy
Sitemap HTML:
An HTML sitemap is provided and is accessible via a link in the footer ofyour website.
The Front-End Checklist is also available in other languages. Thanks for all translators and their awesome work!
- 🇯🇵 Japanese:miya0001/Front-End-Checklist
- 🇪🇸 Spanish:eoasakura/Front-End-Checklist-ES
- 🇨🇳 Chinese:JohnsenZhou/Front-End-Checklist
- 🇰🇷 Korean:kesuskim/Front-End-Checklist
- 🇧🇷 Portuguese:jcezarms/Front-End-Checklist
- 🇻🇳 Vietnamese:euclid1990/Front-End-Checklist
- 🇹🇼 Traditional Chinese:EngineLin/Front-End-Checklist
- 🇫🇷 French:ynizon/Front-End-Checklist
- 🇷🇺 Russian:ungear/Front-End-Checklist
- 🇹🇷 Turkish:eraycetinay/Front-End-Checklist
- 🇩🇪 German:xfuture603/Front-End-Checklist
- 🇵🇱 Polish:mbiesiad/Front-End-Checklist
- 🇮🇩 Indonesian:nniinnoo/Front-End-Checklist
If you have any question or suggestion, don't hesitate to reach me on X:
This project exists thanks to all the people who contribute. (Contribute).
Thank you to all our backers! 🙏 [Become a backer]
Support this project by becoming a sponsor. Your logo will show up here with a link to your website.[Become a sponsor]
About
🗂 The perfect Front-End Checklist for modern websites and meticulous developers
Topics
Resources
License
Code of conduct
Contributing
Uh oh!
There was an error while loading.Please reload this page.
Stars
Watchers
Forks
Sponsor this project
Uh oh!
There was an error while loading.Please reload this page.
Uh oh!
There was an error while loading.Please reload this page.