Alternative Text

Students work together at UNH

Images are used very frequently within documents and on websites. These images may be decorative and used to add visual interest, but many times the images are chosen because they add meaning to the written content. It is important to ensure that all individuals can access the meaning of the images.  

When images are used without Alternative Text (Alt-Text), these images are not accessible to people who cannot access meaning visually. Alt-text is a short description of the intended meaning of visual content. It is not intended to be a very long description, but rather the key meaning someone would get from quickly looking at the image.  

The specific content to include as alt-text varies quite a lot based on the image as well as how the image is being used. For example, the same picture used in different ways would need different alt-text.  

Tips for Creating Alt-Text  

  • Consider the specific context – When it comes to alt-text, context makes all the difference.  You do not need to include all potential information in alt-text, only what is vital to convey the content and purpose of the image. As the intended meaning and purpose changes, so should the alt-text.  
  • As needed mark images as descriptive – Not all images are intended to convey meaning. For example, there might be a picture used to separate a section or because it looks nice. If the image is not intended to convey meaning to the reader, then it should be marked as descriptive. This means a screen reader would skip the content, so you should be careful when you use this option.  
  • Be succinct – Keep it simple when writing alt-text. This should not be a place where you explain all elements of the image, but rather a place where you can quickly identify the intended meaning. If there is a lot to describe, then you should consider writing a longer description that all can access.  
  • Don't need to include "image of" – Commonly when writing alt-text people will include “image of” and then provide the meaning. That is not needed as a screen reader will already identify the element as an image.  
  • As needed include a longer description – If you find that you cannot describe the image in a short and concise way, then you should consider writing a longer description. Often this can be done by simply writing additional content. This way all individuals can benefit from the description.  
  • Should not rely on GIFs for content – GIFs can be made accessible, but it’s not always an easy process depending on the platform on which they are being used. In general, it is best not to rely on gifs as the only means of sharing content.