Alternative text, or alt text, is a crucial component of accessibility and in particular Section 508 to help those using assistive technology get the intent and meaning of images used within a document. As a rule, documents and websites should only use images that help illustrate or enhance the meaning of the content. Remember, we are a government organization and most people are coming to the website for information or a solution to their problems. Decorative images in informational documents, marketing material, and websites should be kept to a minimum not only to minimize confusion, but to create smaller files for faster loading and energy conservation. Clip art from the late 1990s and early 2000s should never be used unless it is a historical document related to imagery on the web.
As mentioned, the purpose of alt text is to convey the meaning of the image in a concise manner. If this image is intended to convey an emotion, explain or describe that emotion. If the image is purely decorative and not intended to convey an meaning mark it as decorative (check box in Office products and Acrobat DC).
- All images must have alt text or be marked as decorative.
- Images intended to convey meaning must have a textual equivalent available.
- Avoid text on images and do not use images that are just text.
- Don't use abbreviations.
- Use punctuation for full sentences.
- Describe the image, such as, “Group of people at an airport.”
- Alt text should consider the context in which the photo is being used and be as meaningful as possible.
- Keep the alt text clear, meaningful and concise (due to screen reader behavior and general useability, the text should be less than 250 characters). If longer text is required to convey the message, use captions or the surrounding text, and then in the alt attribute use very basic text.
- Don’t repeat the text of an adjacent caption. Screen readers read both the caption and the alt text, so avoid having the same details in both.
- End alt text with a period. This signals the screen reader to pause before proceeding.
- If the image is just decorative and conveys no real meaning, use the "Mark as decorative" checkbox. Minimize the use of decorative images - they can be a distraction and they increase the file size.
- If the image is a hyperlink without any text, it must have alt text. If the link includes the image and text, then the empty alt can be used to avoid redundancy.
- Do not use "a picture of," "an image of," "a photo of," "the so-and-so icon." Screen readers tell the user that there is an image and then read the alt text.
- Do begin with “Screenshot of … ” if the image is a screenshot
- Manually check that all alt text is entered correctly, Microsoft auto-generates alt text for images, but this text should be removed unless it has been verified to be correct.
In addition to the technical requirements and general understanding, good alternative text will improve search engine optimization thereby improving access to information.
Resources for writing good alt text
Statement of Endorsement
Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government, and shall not be used for advertising or product endorsement purposes.
Page last updated on February 7, 2022
DigitalVA Accessibility Guide
An official website of the U.S. Department of Veterans Affairs