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When typing in text you want to consider the color contrast between the text and the background. For small text (under size 18), a good contrast ratio to aim for is 4.5:1 or higher. For bigger text (over size 18) a good contrast ratio is 3:1 or higher. Black text on a white background or 21:1 is considered to be the most accessible contrast ratio. If you create a bullet list, the points need to have a contrast ratio above 3:1. Backgrounds with crazy features or patterns should be avoided at all costs. Fortunately, Google Docs does not have any slide themes that are not accessible. To check if your color contrast ratio is sufficient, you should use Adobe’s Color Contrast Analyzer tool.
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This slide above has a contrast ratio of 1.16 : 1. This is very low and hardly visible to most readers. |
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This slide above has a contrast ratio of 21 : 1. |
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This shopping list has grey bullet points and is hard to see. |
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This shopping list has black bullet points and is easy to see.  |
Section 2.2: Using Color to Convey Meaning
If you are going to use color to convey information, always include a text alternative. Color alone is not enough to show off information. For example, color blind users or people with low vision looking at a chart may not be able to read the data or struggle to differentiate the data sections.
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This pie chart for the “Most Popular Sports in the USA” only uses color to represent the data. A person who is color-blind may not be able to tell the difference between the colors. Therefore they cannot read the data. |
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This pie chart for the most popular sports has data labels to represent the data in addition to the color. Now all users can read the data much easier.  |
After your pie chart is finished, you need to provide an alt text for the chart. To do this, right click on the chart. The Format Options Menu will appear to the right of the screen. Click on the Alt Text dropdown menu and type in your alt text.
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The chart has been provided an alt text.  |
Section 2.3: Transitions and Animations
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