Be able to add alternative text/screentip to an object

Presentations – Adding Alternative Text / ScreenTip

Objective

Students will be able to add alternative text (Alt Text) or a ScreenTip to any object in a presentation, ensuring the slide is accessible to all users.

Why it matters

• Alternative text provides a description of visual objects for users who rely on screen‑reading software.
• ScreenTips give additional information when the mouse hovers over an object, useful for clarification.
• Including Alt Text and ScreenTips helps meet accessibility standards and improves the overall quality of the presentation.

Key terminology

• Alternative Text (Alt Text) – A concise description of an object that is read by assistive technologies.
• ScreenTip – A short tooltip that appears when the cursor rests on an object.
• Object – Any shape, picture, chart, SmartArt, text box, or media element on a slide.
• Accessibility – Designing content so that it can be used by people with a wide range of abilities.

Step‑by‑step procedure (Microsoft PowerPoint)

1. Select the object you wish to describe.
2. Right‑click the object and choose Format Shape… (or Format Picture… for images).
3. In the formatting pane, click the Size & Properties icon (the square with measurement lines).
4. Expand the Alt Text section.
5. Enter a brief description in the Title field (optional) and a more detailed description in the Description field.
6. To add a ScreenTip, stay in the same pane, locate the ScreenTip box, and type the text you want to appear on hover.
7. Click Close to apply the changes.

Keyboard shortcuts (Windows)

Best practice checklist

• Keep the description concise (around 125 characters) but informative.
• Avoid phrases like “image of” or “picture of”; the screen reader already identifies it as an image.
• Use simple language and avoid technical jargon unless it is essential.
• For decorative objects that add no meaning, you may leave the Alt Text blank.
• Test the ScreenTip by moving the mouse over the object in Slide Show view.

Common mistakes to avoid

1. Copy‑pasting the same generic description for every object.
2. Including unnecessary visual details (e.g., “blue circle”) when the shape itself conveys the meaning.
3. Leaving Alt Text empty for informative images such as charts or diagrams.
4. Using overly long descriptions that overwhelm screen‑reader users.

Suggested diagram

Assessment activity

Provide each student with a slide containing three different objects (a photograph, a chart, and a decorative shape). Ask them to:

1. Add appropriate Alt Text to the photograph and chart.
2. Leave the decorative shape without Alt Text.
3. Add a ScreenTip to the chart that explains what the data represents.
4. Present the slide in Slide Show mode and verify that the ScreenTip appears correctly.

Extension

Explore how alternative text is added in other presentation software (e.g., Google Slides, LibreOffice Impress) and compare the steps.