As a marketer, you want your website to reach your target audience. You've probably fine-tuned your branding, your messaging, and your value proposition. But what if all of these were on point, but you were unwittingly slamming a door on some of your visitors? In other words, have you been considering the needs of your disabled audience?

People with some type of disability make up 15% of the world's population, according to the World Health Organization. In the United States, the Centers for Disease Control and Prevention estimate that 26% of Americans have a disability. That's 61 million people.

To serve your disabled visitors, you need to be a part of the web accessibility initiative. Web accessibility is about removing access barriers from websites that prevent disabled people from using them effectively.

Disabled web users are a diverse group. Their impairments may fall into one or more of these five categories:

Visual Impairments: blindness, low vision, and color blindness.

Auditory Impairments: deafness and hearing loss.

Motor Impairments: for example, paralysis, limited sensation, or lack of fine motor control.

Cognitive Impairments: including epilepsy, dyslexia, learning disability, autism, ADHD, and more.

Speech Impairments

To cater to this variety of needs, it helps to have a set of web accessibility guidelines. That's where the Web Content Accessibility Guidelines come in.

Download Now: Free Website Accessibility Checklist

The first web accessibility guideline was published in 1995 by technologist Gregg Vanderheiden. Other authors added more web accessibility guidelines to create the Unified Web Site Accessibility Guidelines. This document became the basis of the Web Content Accessibility Guidelines 1.0, which were released in 1999.

WCAG 1.0 contained 14 guidelines. These guidelines included specifying alternatives for audio and video content, avoiding the use of tables for layout, and giving users controls over moving or blinking text.

In the years following WCAG 1.0, there were several changes in the way that people created and used websites. Then, Web 2.0 evolved — a more user-centered, social, and interactive web. People began creating and sharing their own content on the web and social media sites started to gain popularity. Phones were released with internet capability. Websites couldn't just work on desktop computers and laptops anymore — they had to adapt to mobile devices. Table layouts became out of date and responsive web design was born.

As a result of all these changes, the web accessibility guidelines became outdated and needed updating. In December 2008, a complete revision was published, called WCAG 2.0. WCAG 2.0 organized its 12 guidelines around four accessibility principles: perceivable, operable, understandable and robust. WCAG 2.0 became an official standard in 2012.

Launched in 2018, WCAG 2.1 is the latest version. It builds on version 2.0 by adding a new guideline and new criteria to aid users with low vision, users with cognitive issues, and mobile device users.

How the Web Content Accessibility Guidelines are Organized

The Web Content Accessibility Guidelines are built around four principles:

  1. Perceivable: users can consume content via the senses (sight or hearing, sometimes touch).
  2. Operable: users can operate a website with the controls they use normally.
  3. Understandable: websites and user interfaces are comprehensible to users.
  4. Robust: websites should work cross-browser and cross-platform.

We'll go in-depth on each of these principles below.

There are thirteen web accessibility guidelines in all, and each guideline is broken down further into a list of success criteria. The success criteria are designed to be testable measures of accessibility. Each success criterion has a level of A, AA, or AAA. Level A criteria are the easiest criteria to pass and Level AAA are the hardest.

You might see a website described as WCAG 2.0 AA compliant. What does this mean? It means that the site passed all the WCAG 2.0 level A success criteria and the level AA success criteria. Think of it like levels in a video game. You can't complete level two unless you have also completed the whole of level one.

Government websites in many countries have adopted WCAG 2.0 or WCAG 2.1 at level AA as their preferred standard. In the U.S., there have been rulings under the Americans with Disabilities Act (ADA) to say that the ADA applies to websites. As yet, there has not been a consensus on what web accessibility guidelines a website should follow to comply with the ADA.

As it seems highly likely that WCAG will be recommended in future for ADA compliance, it's worth taking the time to understand and apply these web accessibility guidelines now.

1. Provide alternatives for non-text content.

WCAG Guideline 1.1: "Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language."

All non-text content needs a text description to convey the meaning to users who can't see it. This means images, primarily, but also other content such as CAPTCHAS, ASCII art, and emoticons.

The most common method to describe images is through alternative text, commonly known as image alt text. This is a short description added to the HTML code for the image that indicates what it represents.

Most content management systems have a mechanism to add alt text when an image is uploaded.

Adding alt text to an uploaded image in WordPress.


When you write alt text, think how you would describe the image to someone on the phone. You don't need to add the words "image of" or "graphic of". Screen reader software, which blind people use to access the web, notifies users when an image is present. It's okay to add keywords to alt text if they're relevant for SEO. However, stuffing the same keywords in every image on a page is uncalled for.

If an image is decorative, it should have a null alt attribute, i.e., alt="". WordPress, for example, marks an image as decorative (alt="") if you leave the alt text blank.

Linked images are a bit different. They need alt text that details their URL destination, not a description of the image.

House icon.


For example, if this image of a house was linked to a home page, it would need alt="Home", not descriptive alt text like alt="an orange house with a yellow roof and a brown picket fence".

If you're unsure on what alt text to write, you can consult this handy Alt Decision Tree, or Hubspot's guide to image alt text.

2. Provide different options for viewing media content.

WCAG Guideline 1.2: "Provide alternatives for time-based media."

Time-based media refers to audio and video content. If your site has audio or video, it's most likely that they are pre-recorded, so you should supply them with alternative formats when you upload them. These formats will allow your visitors with hearing or visual impairments to access the content.

Audio Media Guidelines

For audio content, providing a transcript is the most common way to provide an alternative format. Transcripts should have a full record of speech that describe other relevant sounds in the recording, like sound effects or music.

Here's a good example from the Founders Unfound podcast:


Video Media Guidelines

To meet the captions requirement, videos should have captions synchronized to the audio. Captions may be open (burned into the video) or closed (able to be toggled on and off).

Here is an example of a closed caption video from HubSpot:


<iframe width="560" height="315" src="" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

A common closed caption format is a .SRT file, which is a text file which is a text file containing the dialog and timings for a video. When you upload a .SRT file alongside your video, it enables your visitors to turn on closed captions if they need them. Try not to rely on auto-captioning, as it may misrepresent some dialogue.

For silent videos or parts of videos without audio, you can add an audio description describing what is happening in the video, e.g., for a video showing how to assemble a piece of furniture.

It's good practice to provide transcripts for videos as well. One big advantage of captions and transcripts is that they can be indexed by Google and help with your SEO.

3. Create content that's can be viewed on different platforms.

WCAG Guideline 1.3: "Create content that can be presented in different ways (for example simpler layout) without losing information or structure."

This guideline has to do with the structure of pages and relationships between elements. Some of the problems can be solved by using the correct HTML code. Using a WYSIWYG editor makes it easy to add this to web pages. Here are three examples of using code for better accessibility.


Using headings makes a page easier to scan. People with vision loss who rely on a screen reader also benefit from headings as they aid navigation. When a section has a heading, screen reader users can jump directly to that section and bypass other parts of the page.

Start with a heading 1 for the page title. Your first subheading will be a heading 2. A further subheading under your heading 2 will be a heading 3, and so on. It's important to use proper headings because text that is bold or enlarged won't be recognized as a heading by a screen reader.

Here's part of the heading structure for a HubSpot post on making a sales plan.There is a single Heading 1, the page title. Each main section has a heading 2, and subsections have heading 3s. In addition, many of the heading 3s are numbered in sequence for clarity.

A HubSpot post on a sales plan with a clear heading structure.



Use bulleted or numbered lists for groups of items. Screen reader software can tell a user how many list items there are, and which one is being read out. Otherwise, screen reader users miss out on that information. Using bulleted or numbered lists may also help your content to be shown in Google's featured snippets.


Emphasize text with bold or italic text to make it stand out. Bold is preferable.

4. Make content easy to hear and see.

WCAG Guideline 1.4: "Make it easier for users to see and hear content including separating foreground from background."

This guideline is about making content easier for people to see or hear.

Use of Color

Don't rely on color alone to convey information, as colorblind people may not be able to make the distinction.

As an example, the UK Government Digital Service deliberately created an inaccessible website. This example taken from the website shows that careless use of color could have serious consequences for colorblind people.

A list of mushrooms – the ones in green are OK to eat and ones in red will kill you.


Underlining links in your content also helps colorblind people. If you don't do this, and your link color and the surrounding text appear too similar to a colorblind person, they won't be able to tell them apart. As a result, they won't click on your links. Underlining links makes them clear.

Audio Control

Does any background audio autoplay on your site? If so, make sure your visitors have a control to stop it or adjust the volume. Speech or music that autoplays and can't be controlled will interfere with screen reader software as it reads a web page.

Minimum Contrast

Ever stared at your screen in sunlight and struggled to make out the words? Chances are it's a contrast problem. Poor color contrast can affect anyone, but particularly people with low vision conditions.

If you have any control over the design, watch the color combinations you use for background and foreground text. Good color contrast increases readability for your users.

To be WCAG AA compliant, WCAG recommends a contrast ratio of 4.5:1 for regular text, and 3:1 for large text. For AAA it's even more strict.

5. Make all functions keyboard accessible.

WCAG Guideline 2.1: "Make all functionality available from a keyboard."

All functionality on a site should be reachable via a keyboard, as not everyone can use a mouse. People who can't use a mouse include those with fine motor control problems, caused by a condition such as Parkinson's disease; those with muscle spasms, as seen in multiple sclerosis; and those with pain in their hands or arms, which can be caused by repetitive strain injury.

Try using the keyboard only for a day to browse the web. Pack away your mouse, or cover your touchpad, and use the tab key to navigate. When you reach a link, check that you can use the enter key to go to the destination. On buttons, check that pressing enter or the space bar performs an action, such as submitting a form.

If you appear to skip some controls when doing this exercise, it might mean that they don't have keyboard support — something that you can raise with a developer. And if you can't tell where you are on the page when you use the tab key, that's another accessibility issue. See WCAG Guideline 2.4: Navigable.

6. Allow users to adjust timing.

WCAG Guideline 2.2: "Provide users enough time to read and use content."

Users should be able to adjust timings on websites if they need more time to complete actions. This is important for elderly users, who may be slower at browsing, motor impaired users, and users who are anxious.

One example of a situation where timing is critical is making a booking. If there's a time limit a user should be allowed to extend it. Another example is alert messages. Users should be permitted to turn off alerts if it would interrupt their browsing, except for emergency messages.

7. Avoid content that blinks or flashes a lot.

WCAG Guideline 2.3: "Don't design content in a way that is known to cause seizures or physical reactions."

People with seizure disorders are sensitive to blinking or flashing content. The advice is to avoid using any content that blinks or flashes more than 3 times a second, as it might trigger a seizure. Be aware that some people are sensitive to the motion effect in parallax scrolling, so you might want to limit its usage.

8. Provide tools to help navigate your website.

WCAG Guideline 2.4: "Provide ways to help users navigate, find content, and determine where they are."

Make it easy for visitors to find their way around web pages by implementing the following five guidelines on your site.

Defining the Page Title

A web page should have a descriptive title that indicates its content in the title tag. A well-written title tag makes it clear to users and search engines what the page is about, can help the page rank higher in search, and assists a visitor to find it when there are multiple tabs open.

You can check the title tag of your page by hovering your mouse over the browser tab. Usually a page title will be the same as the first heading on the page.

Title is How to Share WordPress Posts on WhatsApp.


Descriptive Links

Experienced screen reader users can have pages read to them very fast. Rather than listen to the whole page, they may browse a page by a list of the headings, or a list of links. It's therefore not very helpful for them to hear links that say "Click here" or "more", because they'll have no idea where they go.

A series of Click Here links.



For websites bigger than a few pages, it helps if users have different methods to reach their destination. Some people, such as those with visual impairments or cognitive disabilities, find it easier to use a search facility to find their way rather than a complex navigation menu.

A site map can also be a useful tool. A site map lists all the website's pages in one place grouped by section. Using one makes it easy for users to quickly find what they need.

Part of the site map.


Another aid is breadcrumb navigation. Breadcrumb navigation is like a "You are here" sign, with links letting a visitor know where they've been and how to return home.

Keyboard Focus

A focus indicator, also known as a focus ring or visible focus, is a visible indication on links, buttons, and form fields. Users will see a focus indicator when they use the tab key to navigate a web page. Focus indicators often get overlooked in web design but are essential for sighted keyboard users to find their way. Without a focus indicator, they won't know where they are on a page, and could waste time clicking on links to unknown destinations.

Focus indicators usually show as an outline or a highlight on links, buttons and form fields. In the example below, a dotted outline and a yellow highlight make up the focus indicator on the link. It's an obvious way for the user to see where they are on the page.

The link 2.4.7 Focus Visible is indicated with a dotted outline and yellow highlight.


Section Headings

Having section headings relates back to WCAG Guideline 1.3: Adaptable. Section headings break up the page and increase readability. A web page with a wall of text is not user-friendly and is difficult to read.

9. Accommodate various input options.

WCAG Guideline 2.5: "Make it easier for users to operate functionality through various inputs beyond keyboard."

Guideline 2.5 is new in WCAG 2.1. It considers user input beyond the traditional keyboard and mouse. This includes tapping and gestures on touch devices, and speech input. This guideline's success criteria are more applicable to developers.

10. Ensure text content is grammatically correct.

WCAG Guideline 3.1: "Make text content readable and understandable."

You should aim for all your text content to be easily read and understood by your audience. Below are a few tips.

Check that a web page uses your native language. If you use WordPress, you can define this in your Settings. The language will be applied to all your website's pages.

Site Language English (United States).


Write in plain language where you can. The Hemingway App can help with this. It warns you when your sentences are too complex or when you could use simpler words by highlighting the text in color.

Hemingway app showing writing advice.


If you need to use abbreviations or unusual words, they may not be universally understood, so define them for your readers' benefit. You could include your definition as part of the text, or link to the definition in a glossary.

11. Design predictable website features.

WCAG Guideline 3.2: "Make Web pages appear and operate in predictable ways."

Users expect websites to behave in predictable ways. If the navigation on a website switched order or position on every page, most of us would get very confused. The effect would be heightened for anyone who had low vision, blindness, or a cognitive disability.

One example of unpredictable behavior is if a link is set to open in a new window or tab, and the user isn't warned before they click or tap. This will likely baffle or annoy some users, particularly those with cognitive issues, because they can't use the Back button on the browser to return to where they came from.

12. Offer assistance when users make mistakes.

WCAG Guideline 3.3: "Help users avoid and correct mistakes."

We all have to fill in forms on websites sometimes and often we make mistakes. Tips on completing forms and descriptive error messages help prevent or correct mistakes. Avoid doing the following things and you will make your forms more accessible.

Relying on placeholders instead of form labels. Placeholder text disappears when someone starts typing. Anyone with memory issues may forget what information they were supposed to complete, with the result that they may type in the wrong data or abandon the form completely.

Login form which uses placeholder text rather than labels.


Withholding key information until after the form is submitted. An example is what characters to use when creating a password. If information is quite complex to fill in, people need to know the format first. Otherwise, they can get frustrated with having to repeat their input through no fault of their own.

The advice on creating a password is only shown once the form is submitted.


Failing to mark required form fields as required. It's very frustrating for someone to complete a form and find it fails on submission, because it wasn't obvious which form fields were required and which were optional. Keep your users happy by marking required fields clearly.

Giving unhelpful error messages that don't tell users how to fix their mistakes. "Email address is invalid" tells someone what the error is, but not what to do to correct it. "Your email address is missing the @ symbol" is better, as it gives specific feedback on how to fix the error.

13. Write code that works.

WCAG Guideline 4.1: "Maximize compatibility with current and future user agents, including assistive technologies."

The final guideline of the Web Content Accessibility Guidelines relates to the technical aspects of web pages. It covers these points:

Is the code correct and valid? Browsers are smart and can usually compensate for errors, but screen readers might not be able to recognize controls without the right code.

Are custom controls built in such a way that they can be used correctly? For example, an accordion might not be usable by a screen reader user if poorly coded.

Do users get status messages that let them know of a change as a result of their actions? If a user adds an item to a shopping cart, they should be told as much.

Make Your Site Accessible

Following the Web Content Accessibility Guidelines may feel like a challenge, but the rewards of an accessible website are worth the effort.

You will reach a wider audience because you've thought about and catered to a range of different people's needs. Your website will be more usable because people will find it easier to understand and interact with. Your SEO will likely improve, as using the correct code plus text alternatives to multimedia will delight search engines as well as visitors. You will protect yourself from legal risk and liability that could happen as a result of an inaccessible site.

Finally, you will foster good public relations as you are doing the right thing.

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Originally published Mar 9, 2021 7:00:00 AM, updated March 09 2021


Web Accessibility