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The ISO language code used is a valid

The purpose of this audit is to ensure that the lang attribute used in HTML page elements contains a valid ISO 639 approved language code. The lang attribute is used to indicate the language of the content within the HTML element. By adhering to ISO 639 standards, we can promote accessibility, enhance search engine optimization (SEO), and facilitate the proper interpretation of content by various software applications and systems.

Why it is important?

The utilization of a valid ISO 639 approved code for the lang attribute holds significant importance for the following reasons:

  • Accessibility
  • Search Engine Optimization (SEO)
  • Interoperability
  • Internationalization and Localization


When users with disabilities rely on assistive technologies, such as screen readers or text-to-speech software, the correct identification of the language in which the content is written helps these tools provide accurate pronunciation and presentation. By using a valid language code, we contribute to ensuring that individuals with disabilities can effectively access and comprehend the information presented on the webpage.

It allows braille translation software to substitute control codes for accented characters, and insert control codes necessary to prevent erroneous creation of Grade 2 braille contractions.

Speech synthesizers that support multiple languages will be able to orient and adapt to the pronunciation and syntax that are specific to the language of the page, speaking the text in the appropriate accent with proper pronunciation.

Marking the language can benefit future developments in technology, for example users who are unable to translate between languages themselves will be able to use machines to translate unfamiliar languages.

Marking the language can also assist user agents in providing definitions using a dictionary.

Search Engine Optimization (SEO):

Search engines utilize the lang attribute to determine the language of a webpage's content. By providing a valid language code, we enable search engines to accurately index and rank the webpage for relevant language-specific search queries. This improves the visibility and discoverability of the webpage within search engine results, leading to increased organic traffic and improved user engagement.


Validating the lang attribute against ISO 639 ensures interoperability and compatibility with various software applications and systems that rely on language identification. Web browsers, translation services, language-specific libraries, and content management systems can leverage the language code to provide appropriate language-specific functionalities and processing.

Internationalization and Localization:

In a global context, the correct usage of language codes allows for effective internationalization and localization efforts. Language-specific adaptations, such as translated content, localized user interfaces, or date and number formatting, can be accurately applied based on the identified language. This enhances the user experience for multilingual audiences and facilitates effective communication across diverse cultures and regions.

Validating the lang Attribute

During this audit, Sitefig will review HTML page elements containing the lang attribute to ensure that a valid ISO 639 approved code is used. The ISO 639 standard provides a comprehensive list of language codes that are widely accepted and recognized internationally. It is crucial to adhere to this standard to maintain consistency and compatibility across platforms and systems.

To validate the lang attribute, Sitefig will cross-reference the provided language code with the ISO 639 code list. Any instances where an invalid or non-approved language code is found will be flagged for corrective action. Sitefig recommends referencing the ISO 639-1 or ISO 639-2 standard for a comprehensive list of approved language codes.

By conducting this audit and enforcing the usage of valid ISO 639 approved codes for the lang attribute, Sitefig aims to promote accessibility, improve SEO performance, and facilitate efficient language processing within the web ecosystem.

Please note that the audit does not encompass the correctness of the actual content within the HTML page but focuses solely on the validity of the lang attribute in relation to ISO 639 standards.