Alt Text in PowerPoint Presentations

Presentations rely heavily on visual content to convey information. Alternative text ensures that screen reader users can understand images, charts, shapes, and diagrams that others see on slides.

What This Means

Every meaningful image, shape, SmartArt graphic, and chart in your presentation must have alternative text that conveys the same information that sighted viewers receive.

Why It Matters

• Presentations are highly visual by nature
• Screen reader users miss critical content without alt text
• Charts and diagrams often contain key data that must be accessible
• Professional presentations must be inclusive to all audience members

Common Violations

PPTX-01-001: Image Missing Alternative Text {#PPTX-01-001}

What's Wrong: An image on a slide has no alternative text. Screen reader users will not know the image exists or what it depicts.

Impact: Critical - Visual content is completely inaccessible.

How to Fix:

1. Right-click the image
2. Select Edit Alt Text (or View Alt Text)
3. Enter a description that conveys the same information as the image
4. For decorative images, check Mark as decorative

Example Alt Text:

• "Team photo showing five employees at the company retreat"
• "Product mockup displaying the new mobile app interface"
• "Graph showing customer satisfaction increased from 72% to 89%"

PPTX-01-002: Image Has Empty Alternative Text {#PPTX-01-002}

What's Wrong: The image has an alt text field, but it's empty or contains only whitespace.

Impact: Critical - Empty alt text provides no information.

How to Fix:

1. Right-click the image
2. Select Edit Alt Text
3. Replace empty text with a meaningful description
4. If truly decorative, check Mark as decorative

Decorative Images:

• Background textures
• Decorative borders
• Repeated brand elements (after first occurrence)

PPTX-01-003: Shape or SmartArt Missing Alternative Text {#PPTX-01-003}

What's Wrong: A shape or SmartArt graphic that conveys information doesn't have alternative text.

Impact: Serious - Complex visual information is inaccessible.

How to Fix for Shapes:

1. Right-click the shape
2. Select Edit Alt Text
3. Describe what the shape represents
4. If the shape contains text, describe its purpose

How to Fix for SmartArt:

1. Click on the SmartArt graphic
2. Right-click and select Edit Alt Text
3. Describe:
   • The type of diagram (hierarchy, process, cycle)
   • The relationships shown
   • Key information from each element

Example SmartArt Alt Text: "Process diagram with three steps: 1. Research Phase - gathering market data, 2. Development Phase - building the product, 3. Launch Phase - releasing to market. Arrows connect each phase sequentially."

PPTX-01-004: Chart Missing Alternative Text {#PPTX-01-004}

What's Wrong: A chart on a slide has no alternative text describing the data it presents.

Impact: Critical - Data visualizations are key presentation elements that become inaccessible.

How to Fix:

1. Click on the chart
2. Right-click and select Edit Alt Text
3. Describe:
   • Chart type (bar, line, pie, etc.)
   • What data it shows
   • Key trends or insights
   • Important data points

Example Chart Alt Text:

Poor: "Chart"

Better: "Bar chart of quarterly revenue"

Best: "Bar chart showing quarterly revenue growth: Q1 $2.1M, Q2 $2.5M, Q3 $2.9M, Q4 $3.4M. Revenue increased 62% from Q1 to Q4."

Writing Alt Text for Presentations

Context Matters

The same image might need different alt text depending on its purpose:

• In a product demo: Focus on features shown
• In a company overview: Focus on people or culture
• In a data slide: Focus on the key insight

Slide Notes as Supplement

For complex visuals, use slide notes:

1. Go to View > Notes
2. Add detailed descriptions in the notes section
3. Reference the notes in your alt text: "Process diagram described in detail in speaker notes"

Keep Audience in Mind

• What does this visual help you explain?
• What would someone miss if they couldn't see it?
• What's the key takeaway?

Using PowerPoint's Accessibility Checker

1. Go to Review > Check Accessibility
2. Review "Missing alternative text" errors
3. Click each error to navigate to the element
4. Add alt text following the recommendations

Best Practices

Do:

• Describe the meaning, not just the appearance
• Include data points for charts
• Explain relationships in diagrams
• Use slide notes for complex descriptions
• Mark truly decorative images as decorative

Don't:

• Use "image of" or "picture of" (screen readers announce the type)
• Write overly long descriptions (be concise)
• Describe decorative elements in detail
• Copy the slide title as alt text
• Leave any visual elements without alt text

Additional Resources

• Microsoft: Make your PowerPoint presentations accessible
• W3C WCAG 1.1.1 Non-text Content