Best practices

• Fix broken links ◄
  • W3C link checker
• Spelling and grammar ◄
  • Capitalization
  • Writing Style
  • Word Variations e.g. UK vs US
• Check website in all browsers ◄
  • BrowserShots.org
  • Browserling.com
  • Spoon.net
• Decide on www-subdomain ◄
  • no-www.org score of 'B'
  • ...or www.yes-www.org
  • Handle 'www' in web.config

Mobile

• Mobile-Friendly Test ◄
  • Mobile Friendly checker
• Use 'viewport' meta-tag ◄
  • Don’t Forget the Viewport Meta Tag
  • Make your website mobile friendly
• Use correct input types ◄
  • Input type: Email, Url, Phone
  • Diving in to HTML5 forms
• Manual check using emulators ◄
  • Online media query tester
  • 6 free mobile emulators
  • Opera Mobile Emulator
• Test using real devices ◄
  • Use Open Device Labs to test multiple devices

Analytics

• Uptime monitoring ◄
  • Uptime robot
  • GotSiteMonitor.com
• Traffic analysis ◄
  • Google Analytics
  • StatCounter
  • Clicky
  • Piwik

Performance

• Google Page Speed score of 90+ ◄
  • Google Page Speed
• Optimize HTTP headers ◄
  • redbot.org
• Optimize images ◄
  • kraken.io
  • PunyPNG.com
  • PNGGauntlet for Windows
  • Image Optim for Mac

Usability

mod

• HTML5 compatibility check ◄
  • Compat Inspector
  • modern.IE
  • Modernizr JS library
• Custom 404 page ◄
  • A more useful 404
• Favicon ◄
  • Real Favicon Generator
  • Favicon Cheat Sheet
• Use friendly URLs ◄
  • 11 best practices for URLs
  • URL rewriting in IIS
  • URL rewrite in Apache
• Print-friendly CSS ◄
  • Set up a print stylesheet
• Add search feature ◄
  • Google Custom Search
  • Consider 'Open Search'
• Environment Integration ◄
  • Safari on iOS
  • Internet Explorer on Windows
  • Windows 8 Tiles

Semantics

• Add meaning with structured data ◄
  • Schema.org reference
  • Schema-Creator.org
• Check the semantics ◄
  • W3C semantic extractor
  • Google Structured Data Testing Tool
  • Facebook OpenGraph Debugger
  • Twitter Card Validator

SEO

• SenSEO score of 85+ ◄
  • SenSEO for Firefox
• Google Rich Snippets ◄
  • Online tester
  • Getting started
• robots.txt ◄
  • robots.txt tutorial
  • Create robots.txt online
• XML sitemap ◄
  • Create sitemap online

Code quality

• HTML validation ◄
  • W3C HTML validator
  • Dr. Watson
• CSS validation ◄
  • W3C CSS validator
• Run CSS Lint ◄
  • Run CSS Lint online
• Run JSLint/JSHint ◄
  • Run JSLint online
  • Run JSHint online
• World ready ◄
  • W3C i18n checker
• Automated testing ◄
  • Testomato

Accessibility

• Accessibility validation ◄
  • Common problems and solutions
  • IDI Web Accessibility Checker
  • Test using a screen reader
• Color contrast ◄
  • Check color contrast online
• WAI-ARIA Landmarks ◄
  • Using WAI-ARIA Landmarks
  • Guide to WAI-ARIA
  • Practical examples

Security

• Follow best practices ◄
  • ASafaaWeb security analyzer
  • Observatory by Mozilla
• Cross-site scripting ◄
  • XSS cheat sheet
  • DOM based XSS cheat sheet
  • Free XSS scanner
• Cross-site request forgery ◄
  • Explanation and walkthrough
  • CSRF cheat sheet
• Secure connection (SSL) ◄
  • Setup SSL on IIS 7
  • Setup SSL on Apache
  • SSL Server Test
• HTTP Strict Transport Security ◄
  • MDN Overview
  • OWASP Overview
• Enable Content Security Policy ◄
  • Content Security Policy
  • MDN Guide
  • OWASP Overview
  • CSP Tester

Social Media

• Open Graph protocol ◄
  • Open Graph protocol reference
• Twitter Cards ◄
  • Documentation
• Facebook Insights ◄
  • Facebook Insights
• Google+ ◄
  • Google+ Publisher

...and finally

• Add humans.txt ◄
  • We are humans, not machines!

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