HTML not PDF
HTML Publish in HTML format wherever possible. HTML documents are:
- are easier to find in search engines
- easier to read online because they reformat to fit mobile devices
- easier to keep up to date
- are readable by a wide range of assistive technologies used by people with disabilities
PDF documents:
- can make content harder to find in search engines
- are harder to keep up to date
- do not work well with assistive technologies like screen readers
Creating a new document as PDF is a last resort and should be avoided unless there is a specific business need.
If your published attachments are static, non-editable content for downloading, you must use the PDF/A standard.
Simple language
Use clear and simple language.
Where you need to use technical terms, abbreviations or acronyms, explain what they mean the first time you use them.
For detailed guidelines refer to the Government Digital Service style guide.
Document structure and content
Title Give the document a meaningful title.
Structure Keep the document structure simple. Documents with single continuous columns of text are easier to make accessible than documents with a complex layout.
Sections Break up your document to make it more readable. Use bullet points, numbered steps and meaningful subheadings.
Styles Use styles for tables and bullet lists. That way, a screen reader will recognise the formatting and read out the content correctly.
No bold Do not use bold to mark up subheadings – use styles to create a hierarchy of headings: ‘heading 1’, ‘heading 2’ and so on.
Length Keep sentences and paragraphs short – aim for around 25 words or less per sentence.
Font Use a sans serif font like Arial or Helvetica. Use a minimum size of 12 points. Do not use a smaller size for footnotes, because don't use footnotes.
Footnotes Avoid footnotes where possible. Provide explanations in the body copy instead.
Sentence case Use sentence case in all titles and headings.
Avoid text in capitals, bold or and italics.
left aligned Ensure text is left aligned, not justified.
No underlining Avoid underlining, except for links.
Link text Make sure link text clearly describes where the link goes. It should also be understandable on its own, even if read out of context. This is because some screen reader users list links on a page to find what they need quickly.
Tables, charts and graphics
Tables Only use tables for data. Keep tables simple. Avoid splitting or merging cells.
Colour Do not use colour or shape alone to convey meaning.
Graphs
- do not rely on colour alone to convey information
- use different line styles or types of shading to differentiate between lines or bars
- attach the meaning of bars or lines to the bars or lines themselves, rather than in a separate legend
Read our guide to Accessible charts and graphs for examples of best practice.
Alternative text If you’re using images or charts, think how you’ll make the content accessible to people with a visual impairment.
- make the same point in the text of the document (so people with visual impairments get the information they need - the image or chart is there as an extra for people who are able to see it)
- put a summary of the key points of a chart or table in its alt text
Images with text Do not use images containing text, as it’s not possible to resize the text in the image and screen readers cannot read text which is part of an image.
Infographics Many visually impaired people use screen magnifiers. This means they cannot see the overall design of an infographic and makes it difficult to understand the relationships between visual elements and the information conveyed by the layout and design. Also, most screen readers cannot read text which is embedded in an image.
Therefore, if you're including an infographic in a page, make sure all the important information it conveys is also in the main text.
Sources
Government Digital Service (GDS) accessible document guidelines: