What is web accessibility?

Web accessibility is about making web content that disabled people can use.

On this page

What web accessibility means

Accessible web content is content that has been designed and developed to be easily consumed and interacted with by disabled people. It considers things like:

Fundamentally, web accessibility is about designing web content so that it doesn't present any barriers to disabled people accessing and using it. It supports social inclusion and increases the autonomy, privacy and personal development of disabled people.

For an overview of web accessibility, see this 4-minute video from the W3C, Video Introduction to Web Accessibility and W3C Standards.


On the web, accessibility is sometimes referred to by the numeronym ‘a11y’, often pronounced ‘A-eleven-Y’ or like the words ‘ally’ or ‘alley’. The numeral ‘11’ replaces the 11 letters between the first letter ‘a’ and the last letter ‘y’ of the word ‘accessibility’.

Choice of channels and input modes

Accessible websites work for people who use different senses — be they visual, auditory or tactile — to access information, ensuring that everyone gets the equivalent information, no matter which sense they use.

Accessible websites enable users to navigate and interact with the content using a variety of input modes, such as pointers, keyboards and voice. For these to work, it’s essential that web content has been marked up to be machine readable.

For more information, see the following Knowledge Areas:

Who is web accessibility for?

Web accessibility is defined as a human right by the United Nations, which specifically references the rights of all people to have equal access to ‘information and communications technologies and systems’ in Article 9 of The Convention on the Rights of People with Disabilities (CRPD).

Worldwide, an estimated 1.3 billion people — 16% of the world’s population — have a recognised disability. For more details, see Disability — World Health Organization.

In the 2013 NZ Disability Survey, 24% of New Zealanders identified as disabled. Add to this the consideration that not everyone who is disabled self-identifies as being disabled, and the number is potentially higher. For more details, see Disability Survey: 2013 — Stats NZ.

Types of disabilities

Read the following information from the W3C’s Web Accessibility Initiative (WAI) about the different types of disabilities and the web accessibility barriers that people commonly experience:

Why is web accessibility important?

Video: Why is web accessibility important?
Video transcript

Soft music plays in the background.

At the top of a black screen is the logo for Te Kāwanatanga o Aotearoa New Zealand Government. Underneath the logo is the text ‘Why is web accessibility important?’.

Cut to Callum McMenamin. On-screen text reads ‘Callum McMenamin, Web Standards Consultant, Te Tari Taiwhenua, Department of Internal Affairs’.

Callum McMenamin: “I spend a lot of time on the internet, you know, in my job and in my personal life, and I encounter a wide range of how accessible those systems are. There are some systems that I basically can’t use at all.”

Cut to Daniel Harborne. On-screen text reads ‘Daniel Harborne, NZSL Information and Resources Team Leader, Deaf Aotearoa’.

[Daniel Harborne uses New Zealand Sign Language (NZSL). Here, he communicates through an NZSL interpreter who translates between NZSL and English.]

Daniel Harborne (in NZSL): “If information is relevant to me — I’m a New Zealand citizen, I’m living here — I should be able to expect at bare minimum that there would be captions to videos.”

Cut to a black screen. On the left half of the screen is a blue circle. One quarter of the circle changes colour to yellow. To the right, symbols for visual, hearing, mobility and learning impairments are displayed in sequence.

Narrator: Almost a quarter of New Zealanders self-identify as disabled. They have one or more long term visual, hearing, mobility or learning impairments.

Cut to Paul James. On-screen text reads ‘Paul James, Government Chief Digital Officer, Chief Executive, Digital Public Service, Te Tari Taiwhenua Department of Internal Affairs’.

Paul James: “New Zealanders with disabilities are our whānau, they’re our kaimahi and they’re our customers. So we provide, as New Zealand government, information and services to New Zealanders and they have an entitlement to that information and services as well.”

Cut to Ann-Marie Cavanagh. On-screen text reads ‘Ann-Marie Cavanagh, Deputy Chief Executive, Digital Public Service, Te Tari Taiwhenua Department of Internal Affairs’.

Ann-Marie Cavanagh: “We know that over half of New Zealanders over 65 are disabled, so it’s critical that we make sure that our content that’s delivered through our online channels is easily accessible and that we’re not excluding those communities or those parts of the New Zealand community.”

Cut to footage of a blind person using a computer with a refreshable Braille display.

Narrator: “Disabled people often use special hardware and software called assistive technologies that help them access and interact with web content. Sometimes disabled people need content to be in a certain format, such as captions on a video or sign language translation.”

Cut to Daniel Harborne (in NZSL): “And I thought with the COVID situation, when they brought the interpreters on and they were talking about, tonight we’re going to be locking down the country, you know, things are going to be closing. I remember thinking, okay, I need to go and get some food. I quickly dashed out, went to the supermarket, made sure I had enough food. If I hadn’t had an interpreter on screen at that time and I had to read it in the newspaper the next day, or watch the 6 o’clock news the next day to finally have access to know that everything shut, I would have then gone to the supermarket and the shelves would have been empty by then.”

Cut to footage of a web browser navigating from a page on the NZ Government Web Standards, to a page on the Web Accessibility Standard, to the W3C’s page on the Web Content Accessibility Guidelines (WCAG) 2.1.

Narrator: “The New Zealand Government Web Accessibility Standard requires that public service departments make their websites accessible. This means that each web page needs to meet the internationally recognised Web Content Accessibility Guidelines from the W3C.”

Cut to Ann-Marie Cavanagh: “So it would be important, I think, for agencies to ensure that as you’re building out your digital service delivery and your online service delivery to really start from the get-go to include those New Zealanders with disabilities in that co-creation process.”

Cut to Paul James: “It’s really important that leaders and everyone involved in this work takes a sense of responsibility and obligation to make sure that we do hit those standards of accessibility so that all New Zealanders, including those with disabilities, can access the information and services.”

Cut to Callum McMenamin: “I don’t think everything’s ever going to be perfect. I think it’s always going to take constant effort to make things accessible in the same way it takes constant effort to make information secure and to respect privacy regulations. It takes constant effort, constant expertise. I don’t think there’s going to be a lack of work any time soon.”

Cut to a black screen. At the bottom is the logo for Te Tari Taiwhenua Department of Internal Affairs. Above the logo is the text “learn more at digital.govt.nz”.

Fade to black.

New Zealand Sign Language (NZSL) version

For information about the making of this video, read Walking the talk: Creating an accessible video about web accessibility — Digital.govt.nz.

Benefits of web accessibility to everyone

Web accessibility is essential for people with disabilities and useful for all.

World Wide Web Consortium

To learn about how designing for differences is useful to all, watch these videos from the W3C: Web Accessibility Perspectives — Explore the Impact and Benefits for Everyone.

From a business perspective, case studies show how digital accessibility:

For details, see The Business Case for Digital Accessibility — W3C.

Components of web accessibility

Web accessibility depends on websites, authoring tools and user agents, such as web browsers and assistive technologies, all working together. To learn more, see Essential Components of Web Accessibility — W3C.

Web accessibility standards

The international standards for web accessibility are published by the World Wide Web Consortium (W3C).

Created by the W3C’s international working group, Web Accessibility Initiative (WAI), the standards come in the form of guidelines and technical specifications that address the accessibility requirements for the essential components of web accessibility. For an overview of W3C’s suite of accessibility standards, see W3C Accessibility Standards Overview.

W3C is an international organisation founded in 1994 by the inventor of the Web, Tim Berners-Lee, with the aim of leading the web to its full potential. The W3C’s Web Accessibility Initiative (WAI) seeks to improve the quality of the web so that disabled people can easily use it. For more, see About W3C WAI — W3C.

The Web Content Accessibility Guidelines (WCAG)

WCAG applies to web content, that is, content that’s typically viewed in a web browser. To learn more about the guidelines, see these resources from the W3C:

POUR principles

The requirements in WCAG are organised under 4 key accessibility principles: Perceivable, Operable, Understandable, and Robust (POUR).

The POUR principles aim to ensure that people can perceive, navigate, interact with and understand web content using a variety of tools and technologies. See the W3C’s Understanding the 4 Principles of Accessibility.

For each POUR principle, W3C lists a number of accessibility considerations, and provides examples, technical specifications and user stories for each consideration.


User Agent Accessibility Guidelines (UAAG)

The UAAG guidelines apply to user agents to ensure that disabled people can use them. User agents include:

For more information, see the following resources from the W3C:

Authoring Tool Accessibility Guidelines (ATAG)

The ATAG guidelines apply to web content authoring tools, such as:

For more information, see these resources from the W3C:

Policies and legislation in New Zealand

In 2003, Cabinet directed NZ Government core agencies to meet the NZ Government Web Guidelines (now called ‘Web Standards’). For more, see Web Standards Cabinet Minute and Paper — Digital.govt.nz.

The Web Standards include the Web Accessibility Standard, which requires that web content meet the Web Content Accessibility Guidelines (WCAG) 2.1 at Level AA (subject to a few exceptions).

For a list of other relevant policies, see Legal and policy requirements.