Article Series Summary
- PowerPoint’s design ideas feature is great, but it can worsen the accessibility of your content. It may recommend these behaviours that can exclude members of your potential audience:
- PowerPoint’s accessibility checker often ignores these issues or does not check for them at all.
- In this article we explain why this is important and how to fix it.
PowerPoint’s Design Ideas feature helps us create attractive slides quickly. Unfortunately, some of its suggestions do not follow accessibility best practice, creating barriers that may exclude members of your audience. In this blog post we explain one of these issues and how to fix it. The examples shown here use the default PowerPoint template but are likely to occur whichever template you use.
- Too little contrast between colours will not only make your presentation disagreeable, but it also presents a barrier to many.
- Design ideas will sometimes suggest designs that do not have sufficient contrast between colours.
- While the accessibility checker can check for contrast, it does not consistently identify contrast issues created by design ideas.
- It’s a simple issue to remediate. Once you know what to look for it becomes second nature.
Why is colour contrast important?
More than two million people in the UK live with a visual impairment. Many more have difficulties with their sight. It is crucial that, when we create content, we make accessible colour choices. Many readers will skip over text where its colour has insufficient contrast to the background. When we present text or graphical objects without sufficient contrast we may create barriers to our content for several groups, such as:
- Those who have a visual impairment.
- Those who are colour blind.
- Those whose situation or environment require greater contrast, such as using a phone in bright sunlight, or viewing a projected display in a well-lit room.
The Accessibility Guidelines provide a method to know whether the background colour and text colour have enough contrast. This involves comparing the relative luminance of the two colours. The result is a contrast ratio. The higher the result the greater the contrast.
When we use graphical objects such as graphs or icons we should use a contrast ratio of at least 3:1 between adjacent colours. For text, we should aim for a contrast ratio of at least 4.5:1 or higher between the background colour and the text colour. Ideally, we should target 7:1 or higher contrast ratio when possible.
There are many online colour contrast checking sites online. We recommend whocanuse.com
What does Design Ideas do?
Sometime the choices that Design Ideas makes do not provide sufficient contrast to meet accessibility guidelines. Design ideas suggested the below design. We’ve added boxes containing the contrast ratios of the agenda items. None meet the 4.5:1 minimum requirement.
What about the Accessibility Checker?
The Accessibility Checker tests for colour contrast. Unfortunately, these tests do not pick up failures consistently with Design Ideas created slides.
How can you fix it?
Confirm colours have sufficient contrast.
Use a colour picker tool to determine the background and text colour codes. Microsoft Power Toys is free and has a great colour picking tool. Use whocanuse.com to verify the contrast ratio. Keep it simple by aiming for at least 4.5:1 or higher, ideally 7:1 or higher.
Choose an accessible colour combination
If you need to set a better colour combination, choose a text and background colour that have sufficient contrast.
In cases where the background colour varies, and the text colour remains the same, choose appropriate background colour/s that suit your purposes and have sufficient contrast with the text colour.
For our University colour scheme, use the Colour Accessibility Matrix to check which brand colours have sufficient contrast with each other. Using the colour palette built into Microsoft products? Use the colour accessibility matrix for the Microsoft Standard Palette.
Apply your chosen colour scheme to the relevant part of the design PowerPoint has suggested
- In PowerPoint select the object which has background colour you wish to adjust.
- Select the Format menu.
- Select the Shape Fill button and choose the colour you wish to apply to the shape.
- If you wish to change the text colour, select the Text Fill button and choose the colour you wish to apply to the text.
Using the accessibility checker
When the accessibility checker identifies a contrast issue you can use it to resolve the issue. A good rule of thumb is to use light coloured text with dark coloured backgrounds or vice versa.
Should I use a “pure” white or black background in my slides?
You’ve seen presentations using a cream yellow background, or dark background and heard that this is related to accessibility. We’ll cover this in a future blog post. For now, here are two resources to find out more.
- Optimal colours to improve readability for people with dyslexia
- The answer to a question at the end of this presentation introducing the colour accessibility matrix.
Want to learn more?
- How can I use colour accessibly?
- Accessibility 101: Colour Contrast.
- Colour Contrast and Why You Should Rethink It.
- What is colour contrast accessibility? 5 questions and answers.
- Colour Accessibility.
- Contrast and Colour Accessibility.
- How to check your brand’s colour contrast for accessibility
Read the articles in this series
PowerPoint’s design ideas feature is great, but it can worsen the accessibility of your content. It may recommend these behaviours that can exclude members of your potential audience:
PowerPoint’s Design Ideas feature is a marvellous innovation. It makes slide design quick, simple, and within reach of anyone. Currently, it introduces three issues that can exclude members of your audience. The tips we shared in this post make these issues simple to resolve. If you see these issues in your colleagues’ presentations, send them this article so they will know what to do.
Over to you!
Add your comments, questions, and reflections below. Did we get something wrong? Have an important tip to share? Let us know.