Best practices
Understanding vision impairment
Between 7 and 10 percent of the population live with a visual impairment. What needs do these people have?
The video from Brønnøysund register centre showing how people with reduced vision use digital products
Brønnøysundregistrene, in collaboration with the Norwegian Association of the Blind and Partially Sighted (Blindeforbndet), has explored how people with visual impairments experience using digital products. The film was produced at the end of 2019.
Watch video on player.vimeo.comIn the video above, we meet various individuals who are visually impaired to different degrees and in different ways, or who are completely blind. Note that these users are diverse and have different ways of interacting with digital services. For example, some may:
- magnify content 2–4 times
- reduce size to fit more into a small field of vision
- only see parts of the screen
- rely exclusively on a screen reader
- combine magnification with text-to-speech
- prefer mobile devices and tablets with touchscreens
The challenges these users face could have been avoided if the recommendations in this article were followed. Many of these recommendations also improve the user experience for everyone. They are based on requirements from regulations such as universal design and Elmer, as well as best practices and insights from user testing.
Ensure good contrast between text, symbols, and backgrounds
Aim for higher contrast ratios than the minimum required by regulations. Note that some colours may appear to have stronger or weaker contrast than calculations suggest, because we perceive colours differently even when they emit the same amount of light.
Do not rely solely on colour to convey information
Colours can be hard to distinguish for people with colour blindness, so it is problematic to use them alone to communicate important information, statuses, or other content. Always use symbols and text as the primary method, and use colour as a supplement.
Place content and functions on the left
Starting content from the left edge can make it easier for some users to locate and move the cursor to click or select. For more complex interfaces, such as apps or dashboards, left-align within sections and design the solution using grids and subdivisions. This makes it easier to see and distinguish different parts.
Be consistent in placing content and functions
Ensure that features and content remain in the same location across different pages and services. This makes the service more predictable for users who can only see parts of the content at a time.
Place elements so that the order is the same both visually and in code. This allows screen reader users to describe placement and sequence in a way that sighted users can follow (and vice versa).
Avoid unnecessary decorative elements
Limit the use of images and visual elements that do not add value to the content. Too many decorative details can be distracting, and make the solution cluttered and difficult to use.
Font selection
For people with visual impairments, fonts with many small details, such as serif fonts, can be challenging to read. Sans-serif fonts like Arial, Helvetica, Open Sans, or Inter are generally better. However, check that similar-looking letters in these fonts (such as lowercase “l” and uppercase “I”) are distinguishable.
