The Front-End Checklist is an exhaustive list of all elements you need to have / to test before launching your site / page HTML to production.
It is based on Front-End developers' years of experience, with the addition from some other open-source checklists.
All items in the Front-End Checklist are required for the majority of the projects, but some elements can be omitted or not essential (in case of an administration web app, you may not need RSS feed for example). We choose to use 3 levels of flexibility:
means that the item is recommended but can be omitted in some particular situations.
means that the item is highly recommended and can eventually be omitted in some really particular cases. Some elements, if omitted, can have bad repercussions in terms of performance or SEO.
means that the item can't be omitted by any reason. You may cause a dysfunction in your page or have accessibility or SEO issues. The testing priority needs to be on 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
Notes: You can find a list of everything that could be found in the
<head>of an HTML document.
- Doctype:
<!-- Doctype HTML5 -->
<!DOCTYPE html>The next 3 meta tags (Charset, X-UA Compatible and Viewport) need to come first in the head.
- Charset:
<!-- Set character encoding for the document -->
<meta charset="utf-8">- X-UA-Compatible:
<!-- Instruct Internet Explorer to use its latest rendering engine -->
<meta http-equiv="x-ua-compatible" content="ie=edge">- Viewport:
<!-- Viewport for responsive web design -->
<meta name="viewport" content="width=device-width, initial-scale=1">- Title:
<!-- Document Title -->
<title>Page Title less than 65 characters</title>- Description:
<!-- Meta Description -->
<meta name="description" content="Description of the page less than 150 characters">- Favicons:
favicon.ico, put it at the root of your site. Normally you won't need to use any markup. However, it's still good practice to link to it using the example below. Today, PNG format is recommended over.icoformat (dimensions: 32x32px)
<!-- Standard favicon -->
<link rel="icon" type="image/x-icon" href="https://example.com/favicon.ico" />
<!-- Recommended favicon format -->
<link rel="icon" type="image/png" href="https://example.com/favicon.png" />- Apple Touch Icon:
<!-- Apple Touch Icon -->
<link rel="apple-touch-icon" href="/custom-icon.png">- Canonical:
rel="canonical"to avoid duplicate content.
<!-- Helps prevent duplicate content issues -->
<link rel="canonical" href="https://example.com/2017/09/a-new-article-to-red.html">- Language tag:
<html lang="en">- Direction tag:
<html dir="rtl">- Alternate language:
<link rel="alternate" href="https://es.example.com/" hreflang="es">- Conditional comments:
📖 About conditional comments (Internet Explorer) - MSDN - Microsoft
-
RSS feed:
-
CSS Critical:
<style></style>in a single line (minified).
- CSS order:
<head>. (Except the case, where sometimes JS files are loaded asynchronously on top of your page).
Facebook OG and Twitter Cards are, for any website, highly recommended. The other social media tags can be considered if you target a particular presence on those and want to ensure the display.
- Facebook Open Graph:
<meta property="og:type" content="website">
<meta property="og:url" content="https://example.com/page.html">
<meta property="og:title" content="Content Title">
<meta property="og:image" content="https://example.com/image.jpg">
<meta property="og:description" content="Description Here">
<meta property="og:site_name" content="Site Name">
<meta property="og:locale" content="en_US">
- 📖 A Guide to Sharing for Webmasters
- 🛠 Test your page with the Facebook OG testing
- Twitter Card:
<meta name="twitter:card" content="summary">
<meta name="twitter:site" content="@site_account">
<meta name="twitter:creator" content="@individual_account">
<meta name="twitter:url" content="https://example.com/page.html">
<meta name="twitter:title" content="Content Title">
<meta name="twitter:description" content="Content description less than 200 characters">
<meta name="twitter:image" content="https://example.com/image.jpg">
- 📖 Getting started with cards — Twitter Developers
- 🛠 Test your page with the Twitter card validator
- HTML5 Semantic Elements:
- Structured Data:
📖 Introduction to Structured Data | Search | Google Developers 🛠 Test your page with the Structured Data Testing Tool
- Error pages:
- Noopener:
target="_blank"on your links,rel="noreferrer noopener"is present on the<img>. - Clean up comments:
- W3C compliant::
- HTML Lint:
-
Desktop Browsers:
-
Mobile Browsers:
-
Link checker:
- Adblockers test:
- Pixel perfect:
- Webfont format:
- Webfont size:
Notes: Take a look on CSS guidelines and Sass Guidelines followed by most Front-End developers. If you have a doubt on CSS properties, you can visit CSS Reference.
- Responsive Web Design:
- CSS Print:
- Preprocessors:
- Unique ID:
- Reset CSS:
- 📖 Reset.css
- 📖 Normalize.css
- 📖 Reboot
- JS prefix:
<div id="js-slider" class="my-slider">
<!-- Or -->
<div id="id-used-by-cms" class="js-slider my-slider">- CSS embed or line:
- Vendor prefixes:
- Concatenation:
- Minification:
- Non-blocking:
- Unused CSS:
- 🛠 UnCSS Online 🛠
- 🛠 PurifyCSS
- Stylelint:
-
Responsive web design:
-
CSS Validator:
- Debug CSS:
🛠 Debug CSS (you can use the bookmarklet)
- Reading direction:
Notes: For a complete understanding of image optimization, check the free ebook Essential Image Optimization from Addy Osmani.
- Optimization:
- 🛠 Imagemin
- 🛠 Use ImageOptim to optimise your images for free.
- Retina:
- Sprite:
- Width and Height:
<img>have height and width set (Don't specify px or %).
Note: Lots of developers assume that width and height are not compatible with responsive web design. It's absolutely not the case.
- Alternative text:
<img>have an alternative text which describe the image visually. - Lazy loading:
- JavaScript Inline:
- Concatenation:
- Minification:
.minsuffix).
- Non-blocking:
asyncor deferred usingdeferattribute.
- Modernizr:
<html>tag.
- ESLint:
- Weight page:
- Minified:
- Lazy loading:
- Google PageSpeed:
Notes: You can watch the playlist A11ycasts with Rob Dodson 📹
- Progressive enhancement:
- Color contrast:
- H1:
- Headings:
📹 Why headings and landmarks are so important -- A11ycasts #18
- Role banner:
<header>hasrole="banner" - Role navigation:
<nav>hasrole="navigation" - Role main:
<main>hasrole="main"
- Specific HTML5 input types are used: This is especially important for mobile devices that show customized keypads and widgets for different types.
- Label:
aria-labelinstead.
- Accessibility standards testing:
- Keyboard navigation:
- Screen-reader:
- Focus style:
- Google Analytics:
- Headings logic:
- sitemap.xml:
- robots.txt:
- Sitemap HTML:
Open an issue or a pull request to suggest changes or additions.
The Front-End Checklist repository consists of two branches:
This branch consists of the README.md file that is automatically reflected on the Front-End Checklist website.
This branch will be used to make some significant changes to the structure, content if needed. It is preferable to use the master branch to fix small errors or add a new item.
Check out all the super awesome contributors.
David Dias, Geoffrey Signorato, Sandeep Ramgolam and Cédric Poilly.
