Quality Test

Web site tracking
Check that Google Analytics and other tracking services are tracking visits

W3C validation
Verify HTML using http://validator.w3.org

Browser compatibility and accessibility

Site must look according to design in:

IE9
IE8
Firefox
Latest version of Google chrome
Latest version of Safari
Latest version of Opera

Performance optimization
Analyze with Google PageSpeed.
Have you performed a stress test?
Pages checked for byte size.

Various
Check that you have a Fav icon.
Check the add2screen icons
Pages look ok when printed.
Site map is present
Registration form and email activation are ok
Form validation makes sense.
Password recovery is ok
Contents upload from users works fine (eg. Letters, galleries...)
if the site is present on Google News, the name is correctly setted
Sharing of contents works fine
Social login works fine
If social connector is active, everrthing works fine
Comments on contents are working fine
RSS feeds are ok

SEO
Meaningful page titles on all tpe of pages and all meta tags are present

Images & Media
Images can be uploaded correctly
Images that are auto resized are correctly resized.
Images are not large in byte size relative to its screen size

Error pages
404 page (page not found) works.
No results in search display meaningful feedback.

Search
Make sure you can find all type of content that makes sense.
Search based on channels is working fine
Verify that non published content do not appear. 
The number of results is correct.

Accessibility
Site tested on different screen resolutions.
Tested on tablets (Android ones + iPad).
Tested on smart phone.
All links that are not obvious have Title attribute set.

check with Google
right click on the site, select inspect > Audits > Run an audit (enable only Accessibility)

Check if the colors contrast (text/background) is in the standard required:
https://dequeuniversity.com/rules/axe/2.2/color-contrast?application=lighthouse

Viewport on mobile has to have maximum scale to 5
In configuration module change “viewport_mobile” to: “width=device-width, initial-scale=1, maximum-scale=5”

Security
Robots file is well configured
Need to set up e-mail or SMS alerts for uptime monitoring

Content publishing
Quotes works fine in the html backend editor
Images in text are working in the html backend editor
Other text formatting is good
Language specific characters / special characters in different places (e.g. content, search, forms, navigation etc) 

Content
No empty pages are present
No Lorem Ipsum pages are present
Alt text on images is ok
You have contact info, privacy, feedback, terms, cookies and copyright info.
Site tested with realistic content.
Site checked for missing resources (404 on images , js, etc.).

Link from facebook and other social network

enable redirect panel

Design
Navigation is intuitive.
Colors look good on your screen also.
The most important pages are linked to from the front page.
Designed with the reader/user in mind. Lets the user find what he is looking for fast. (Call to action)

Related contents are present