Automatically test a webpage for accessibility issues

The Issues tool includes an Accessibility section that automatically reports issues such as missing alternative text on images, missing labels on form fields, and insufficient contrast of text colors. The Issues tool is within the Drawer at the bottom of DevTools. This article uses the accessibility-testing demo webpage to step through using the Accessibility section of the Issues tool.

There are several ways to open the Issues tool, such as:

  • Click the Issues counter (Issues counter) in the upper right of DevTools.

  • In the Elements tool, in the DOM tree, press Shift while clicking a wavy underline on an element.

  • In the Command Menu, type issues, select Show Issues, and then press Enter.

View the Accessibility section of the Issues tool

  1. Open the accessibility-testing demo webpage in a new window or tab.

  2. Right-click anywhere in the webpage and then select Inspect. Or, press F12. DevTools opens next to the webpage.

    In the upper right, the Issues counter (Issues counter) appears. The Issues counter is a speech-bubble icon along with the number of automatically detected issues.

    The Issues counter in DevTools, indicating how many problems there are in the current document

  3. Refresh the page, because some issues are reported based on network requests. Notice the updated count in the Issues counter.

  4. Click the Issues counter. The Issues tool opens, in the Drawer at the bottom of DevTools.

    Accessibility warnings displayed in the Issues tool

  5. On the Issues tab, expand the Accessibility section.

Verify that input fields have labels

To check whether input fields have labels connected to them, use the Issues tool, which automatically checks the entire webpage and reports this issue in the Accessibility section.

  1. Open the accessibility-testing demo webpage in a new window or tab.

  2. Right-click anywhere in the webpage and then select Inspect. Or, press F12. DevTools opens next to the webpage.

  3. In the upper right, click the Issues counter (Issues counter). The Issues tool opens, in the Drawer at the bottom of DevTools.

  4. On the Issues tab, expand the Accessibility section.

  5. Expand the Warning Form elements must have labels: Element has no title attribute Element has no placeholder attribute.

  6. Click the Open in Elements link.

    Elements tool showing the problematic HTML after clicking the link in the Issues tool

    The Elements tool opens, with the element highlighted in the DOM tree. The Styles pane displays the applied CSS rules for the element.

    The following code is now displayed:

    <label>Search</label>
    <input type="search">
    <input type="submit" value="go">
    

    In the above code, the label element is used incorrectly, because there is no connection between the label element and a particular input element. To connect the label element to a specific input element, use any of the following options:

    • Nest the input element within the label element.

    • In the label element, add a for attribute that matches an id attribute of the input element.

There's also another way to test for lack of connections between elements:

  1. In the Elements tool, select the <label>Search</label> element in the DOM tree.

    On the webpage, notice that focus only appears on the Search label, and not the input text box. The correct implementation would put focus on the search input text box and the Search label.

  2. As an example of a correct connection, select the Other label on the donation form.

    A focus-indicator box correctly appears on the input text box next to the Other label, because there are matching for and id attribute values.

  3. In the Issues tool, click the Further reading to learn more about the issue. To open the link in a new tab, press Ctrl (Windows, Linux) or Command (macOS) while clicking the link.

    Link on the Issues tab pointing to more in-depth information about the issue

Verify that images have alt text

Basic accessibility testing requires making sure alternative text (also called alt text) is provided for images.

To automatically check whether alt text is provided for images, use the Issues tool, which has an Accessibility section. The Issues tool is located in the Drawer at the bottom of DevTools.

  1. Open the accessibility-testing demo webpage in a new window or tab.

  2. Right-click anywhere in the webpage and then select Inspect. Or, press F12. DevTools opens next to the webpage.

  3. In the upper right of DevTools, click the Issues counter. The Issues tool opens.

  4. On the Issues tab, expand the warning Images must have alternate text: Element has no title attribute. There are four instances of images that lack alt text:

    The Issues tool reporting images that are missing alternative text

See Images must have alternate text.

Verify that text colors have enough contrast

To automatically check whether text colors have enough contrast, use the Issues tool, which has an Accessibility section. The Issues tool is located in the Drawer at the bottom of DevTools.

  1. Open the accessibility-testing demo webpage in a new window or tab.

  2. Right-click anywhere in the webpage and then select Inspect. Or, press F12. DevTools opens next to the webpage.

  3. In the upper right of DevTools, click the Issues counter. The Issues tool opens.

    There might be warnings that two elements on the demo webpage don't have enough contrast.

    Contrast problems reported in the Issues tool

  4. Depending on your settings, the Issues tab might have a warning like Users may have difficulties reading text content due to insufficient color contrast. You can expand that warning, and then expand Affected resources. A list of elements appears with a list of elements that don't have enough contrast.

  5. Click the li.high element. In the rendered webpage, the Dogs link in the Donate section is highlighted, displaying a small information overlay. This is the same overlay that appears when you hover over an element in the DOM tree in the Elements tool.

    Element in the webpage highlighted after clicking a link in the Affected Resources section

Wavy underlines in the DOM tree indicate automatically detected issues

The DOM tree in the Elements tool flags issues directly in the HTML with wavy underlines. These issues are reported by the Issues tool. When you press Shift while clicking any element with a wavy underline, the Issues tool opens.

  1. In the Elements tool, in the DOM tree, press Shift while clicking the element <input type="search">, which has a wavy line under input. The Issues tool is displayed, and shows the issue for that element.

    An element that has a wavy underline in the DOM view has an issue

See also