Diagrams are graphics that can help explain information or enhance understanding including:

• process maps
• flow charts
• timelines
• decision trees

Diagrams can be a useful illustrative tool but can present issues with accessibility and text duplication. 

All diagrams must be created by the Digital Publishing Design team. 

Diagrams do not include data. If you are trying to visualise something that involves data, please contact the Data Visualisation team. 

Diagrams and accessibility

Users of all levels of expertise have accessibility needs and use screen readers and other assistive technology. Assistive technology cannot read images. Those using these tools will require the information to be provided as alt text.

We have a legal obligation to make our content accessible. More information is available in our accessibility statement.

Using text instead of a diagram

We recommend using text structured under headings and subheadings instead of a diagram because it means that:

• the content is accessible to more users
• the content can easily be updated
• users can zoom and alter the size of text
• search engines can read the text and display in search results
• it displays better on a mobile device than an image

Any diagram must add a level of explanation and value beyond what can be conveyed by written text.

This diagram could simply be rewritten as plain text which would be clearer and more accessible.

The following conventions are against house style as they are obstacles to accessibility:

• symbols such as “&” and “/”
• directional text
• images and charts without alt text
• superscript after dates such as “st” and “th”
• blank cells in tables
• carousels of images
• walls of text
• text tables

The use of a diagram should only be considered in certain more complex cases. For example, when you need to visualise a complicated process with multiple elements that relate to each other.

Contact content.design@ons.gov.uk at the earliest opportunity to discuss if a diagram is appropriate for your content.