Manually testing a website is a critical step in ensuring that screen reader users can successfully access and understand its content. While automated tools can help identify certain accessibility issues, they cannot fully replicate the real experience of navigating a site without a mouse.
Keyboard-based testing provides a simple and effective way to simulate how many users interact with assistive technologies. There are five fundamental commands designers and developers need to know in order to move around the website using only the keyboard.
By learning a small set of fundamental keyboard commands, developers and designers can gain valuable insight into how their websites function for screen reader users and identify barriers that may otherwise go unnoticed.
The Tab Key
Pressing the tab key allows the user to move forward and focus on the interactive elements on the page. Interactive elements are links, buttons, text input fields and checkboxes. As the user presses the tab key, the browser should indicate where they are currently focused on, often through a colored outline or highlight. This focus indicator is vital for users with low-vision who use screen readers as a supplement to what they see.
Developers can and should audit accessibility issues by navigating the page using the tab key. First, developers should validate that pressing the tab moves them to the next interactive element on the page.
Second, developers should make sure that there is a focus indicator around the element. Third, developers should make sure that the order of the tab is going down the page in a logical order. These are basic accessibility tests developers should complete and fix.
Shift + Tab
While Tab Key moves the user forward, Shift + Tab will move them backwards. Similar to the Tab key behavior, Shift + Tab focuses on interactive elements on the page, but goes backwards. We should make sure that Shift + Tab allows us to move backwards in a logical order. There are many reasons to use Shift + Tab.
For example, we moved too fast to the next interactive element and we want to go back to the previous one. When filling a form, we might make a typo and need to go backwards. When testing for accessibility, developers should make sure Shift + Tab works as intended.
Enter
The enter key is how the user activates the interactive elements. While tabbing through the page, if the user wants to click on a link they are focused on, they should be able to press the enter key to activate it. Similarly, when filling out a form, the user can click on enter to submit the form when we are ready.
When manually testing for accessibility, it’s important to check that the Enter key is completing the action we are focused on. For example, if we are focused on a link, clicking on the link should navigate us to the next page. If pressing enter does not complete this action, there is a problem.
Spacebar
Enter key is usually to “go somewhere”. Spacebar on the other hand is to change something on the current screen that we are on. For example, we can click on the spacebar when we are on top of a checkbox or radio buttons.
Pressing the spacebar will either add a check to the checkbox or remove it. While we are on a checkbox or a radio button, it’s important to make sure that these elements announce to screen reader users their “current state” as in if they are checked on or off. This will allow the screen reader user to make a decision whether to press the spacebar or not.
Arrow Keys
Tab and Shift + tab move the focus to interactive elements and skip everything in between. If we want to read the page, we can click on the up or down arrow keys. Arrow keys will move the focus line-by-line, allowing the screen reader users to read the content. By using the Up and Down arrow keys, users can move sequentially through paragraphs, headings, and other content elements.
This method of navigation also allows screen readers to announce alternative text for images, providing context for visual content that would otherwise be inaccessible. Ensuring that all meaningful images include descriptive alt text is a key part of accessibility, and arrow key navigation is one of the primary ways users encounter this information.
Conclusion
Taken together, these five keyboard commands—Tab, Shift + Tab, Enter, Spacebar, and the Arrow keys—form the foundation of manual accessibility testing. They allow developers to experience their websites from a different perspective and identify issues that may not be immediately obvious through visual inspection alone.
By consistently testing with these keys, teams can create more inclusive and user-friendly digital experiences. Accessibility is not just a technical requirement; it is a commitment to ensuring that all users, regardless of ability, can interact with and benefit from the web.