Goal
- Cultivate content indexing by language.
- Facilitate machine translation.
- Enable correct reading of the content by a synthesized speech tool.
- Improve the accessibility of content for people with disabilities.
- Improve the way content is taken into account by search engines and indexing tools.
Implementation
Fill in the lang
attribute of the html
root element using the appropriate language code (as indicated in the registry maintained by IANA: http://www.iana.org/assignments/language-subtag-registry). In practice, for French this is: <html lang="fr"> (in HTML) et <html lang="fr" xml:lang="fr"> (in XHTML).
Otherwise, in more complex cases, the content language can be indicated by the different parent elements: head
, body
, title
, etc.
Find out more:
Control
Verification consists in checking that the lang attribute of the html
element is present and relevant (or failing that check its descendant elements) in the source code.
In the source code of each page:
- Check that the default language of the content is indicated by the
lang
attribute of thehtml
element, for example <html lang="fr"> (in HTML) - If not, check for each content element that is is at least inherited form a parent element (
head
,body
,title
, etc.) from itslang
attribute.
Check the validity and relevance of the language code used. For this, use for example the Language Subtag Lookup Tool by Richard Ishida, https://r12a.github.io/app-subtags/.
Common cases of incorrect language codes include jp
instead of ja
for Japanese, lu
instead of lb
for Luxembourgish, gr
instead of el
for Greek, lat
instead of la
for Latin, and oci
instead of oc
for Occitan. Additionally, the codes mul
for "multiple languages" and und
for "undetermined language" must not be used in web content. Finally, the xml:lang
can also be entered in addition to the lang
attribute, but it is not sufficient to comply with this best practice.
Overview and background
The 240 Opquast rules are defined and agreed upon by an extensive community of web professionals and academics. These web quality assurance guidance rules started as a list of best practices 20 years ago. They have since been revised every five years and have been tried and tested via millions of web interactions by Opquast community’s customers, including the leading CMS communities which have developed plugins for WordPress, Drupal and Prestashop. The most recent version, v4, was established in 2020.
Each rule has individual technical sheets and the rules can be searched by project phase or various topics: e-commerce, data-privacy, internationalization, security, code, etc, or by themes: accessibility, SEO, mobile, privacy, and ecodesign. The complete checklist is available on a creative commons license BY-SA.
To learn more about the Opquast approach, read this article published at Smashing Magazine
Broad application and benefits
The rules should be applied to your projects from the design phase through to post-implementation , and they should be understood by all professionals with web and customer experience (CX) responsibilities: from strategy to operations, marketers to project managers, and editorial to technical staff. The benefits of using this ruleset are numerous, including improving customer satisfaction, web performance, and e-commerce, and expanding your client base, while also decreasing your errors and costs.

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