If a picture is worth a thousand words, what's it worth to people who cannot see? Without words, it's easy for people with a visual disability to miss critical information or get frustrated with the experience.
Alternative text (alt text) is descriptive text which conveys the meaning and context of a visual item in a digital setting, such as on an app or web page. When screen readers likeMicrosoftNarrator, JAWS, and NVDA reach content with alt text, the alt text is read aloud sopeople can better understand what'son the screen. Well-written, descriptive alt text dramatically reduces ambiguity and improves user experience.
This topic describes how to understand, write, and use effective alt text in Microsoft 365 products.
To help you with alt text, Microsoft 365 offers the Accessibility checker to review relevant visual content for alt text and get suggestions on improving content accessibility, an Automatic alt text generator, and a manual alt text editor.
On the Review tab, select Check Accessibility.
In the right Accessibility pane, issues with accessibility appear under Inspection Results.
Select any flagged issues to see recommended actions.
Right-click an image, chart, or other object, and select View Alt Text.Tip: On the Review tab, you can select the Check Accessibility drop down and choose Alt Text.
In the Alt text pane on the right, edit or approve the displayed alt text (if automatically generated).
If the image doesn't needalt text, such as a border, select Mark as decorative.
On the File tab, select Options and choose the Accessibility tab.
Select or clearthe Automatically generate alt text for me checkbox under Automatic Alt Text.
Automatic alt text generation needs Microsoft 365 intelligent services. To turn this on:
On theFiletab, selectOptionsand chooseGeneral.
SelectEnable servicesunder Microsoft 365 intelligent services.
Make sure to convey the content and the purpose of an image in a concise and unambiguous manner. The alt text shouldnt be longer than a sentence or twomost of the time a few thoughtfully selected words will do. Consider what is important about an image. For example, important context might be the setting, the emotions on people's faces, the colors, or the relative sizes.
Do not repeat the surrounding textual content as alt text or use phrases referring to images, such as, "a graphic of" or "an image of." In the example below, the alt text is referring to the image and does not describe the content of the image sufficiently.
You can also add alt text as an argument to the IMAGE function either by using text in quotes or by using a cell reference that contains the text.For example, IMAGE("www.contoso.com/logo.jpg", "Contoso logo").
When dealing with objects that give detailed information, such as an infographic, use alt text to provide the information conveyed in the object. Describing a chart as A bar chart showing sales over time,' for example, would not be useful to a blind person. Try to convey the insight; for example, A bar chart showing sales over time. In July, sales for brand A surpassed sales for brand B and kept increasing throughout the year. Alt text should also clearly describe the beginning point, progress, and conclusion of flow charts.
Videos that don't explain their content require alt text to describe the visual experience, even if the user hears music, background sounds, and speech. Alt text should describe the content and purpose of the video.
Ideally, a video should contain a second audio track with a description of the video elements that are purely visual and not accessible to people with a visual disability.
The Microsoft 365 Accessibility Checker does not flag if a table is missing alt text. However, it is always a good practice to write a clear, descriptive, and concise alt text for a table.
Decorative objects add visual interest but arent informative (for example, stylistic borders). People using screen readers hear these are decorative so they know they arent missing any important information. To mark a visual as decorative, select the Mark as decorative checkbox in the Alt Text pane. The text entry field becomes grayed out.
Tip:If you export your document as a PDF, any visuals you have marked as decorative are automatically tagged as artifacts. They are then ignored by screen readers when navigating through PDFs.
If the Microsoft 365 Accessibility Checker doesn't flag an object when it's missing alt text, you don't have to write alt text for it. A slicer isan exampleof such an object.
For instructions on how to add alt text inOutlook, Word,Excel, andPowerPoint, go toAdd alternative text to a shape, picture, chart, SmartArt graphic, or other object.
Remember to use the Microsoft 365 Accessibility Checker during your review process. It checks that all relevant visual content has alt text and also gives you other suggestions for improving the accessibility of your content, such as checking contrast ratios. To run the Accessibility Checker, onthe Review tab, selectCheck Accessibility. For more info on the Accessibility Checker, go to Improve accessibility with the Accessibility Checker.
Do not use a file name, duplicate text, or URLs as alt text. The Accessibility Checker flags these since they are not useful to someone with a visual disability. For more info, go to Rules for the Accessibility Checker.
If there is a group of objects that forms a semantic group, such as a group of photos that all show dogs, assign alt text for the whole group. If objects have been grouped together for formatting reasons, ungroup the objects and assign appropriate alt text for each object.
Note:If you have used Microsoft 365 for a while, you might have noticed that the Alt Text pane used to have two fields, Title and Description. Now we use a single Description field in most of our appsit has been found that having a single field is easier and less confusing for both you as the author and also anyone using a screen reader to consume the content.
In Microsoft 365, alt text can be generated automatically. When you insert a picture, you might see a bar show up at the bottom of the picture with automatically generated alt text.
In Office 2019, alt text is not generated automatically when you insert an image. If you want to add automatic alt text, select the Generate a description for me button in the Alt Text pane. Depending on the content of the image, sometimes the feature gives you descriptive tags and sometimes you get full sentences.
If automatic alt text is generated, remember to review and edit it in the Alt Text pane and remove any comments added there such as "Description generated with high confidence."
Note:Before you can use automatic alt text, you might have toenable Microsoft 365 Intelligent Services in any Microsoft 365product.
1.On theFiletab, selectOptionsand chooseGeneral.2. SelectEnable servicesunder Microsoft 365 intelligent services.
For more info, refer toConnected experiences in Microsoft 365.
On theFile tab, selectOptions and choose Accessibility.
SelectAutomatically generate alt text for meunder Automatic Alt Text.
In the Microsoft 365app, right-click the item to reviewand select View Alt Text. The Alt Text pane opens.
If the alt text is satisfactory, select the Approve alt text checkbox.
On theFile tab, selectOptions and choose Accessibility.
ClearAutomatically generate alt text for meunder Automatic Alt Text.
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Everything you need to know to write effective alt text