Alt Text in Excel Workbooks

Alternative text in Excel is essential for making charts, images, and visual elements accessible to screen reader users. Without alt text, these visual elements are invisible to users who cannot see them.

What This Means

Every chart, image, SmartArt graphic, and diagram in your Excel workbook must have alternative text that conveys the same information that sighted users receive from the visual.

Why It Matters

• Charts often contain critical data that must be accessible
• Screen readers cannot interpret visual data representations
• Alt text provides equal access to data insights
• Many spreadsheets rely heavily on visual elements for communication

Common Violations

XLSX-01-001: Chart Missing Alternative Text {#XLSX-01-001}

What's Wrong: A chart in the workbook has no alternative text. Screen reader users cannot understand the data the chart presents.

Impact: Critical - Key data insights are completely inaccessible.

How to Fix:

1. Click on the chart to select it
2. Right-click and select Edit Alt Text (or View Alt Text)
3. In the Alt Text pane, describe:
   • The type of chart (bar, line, pie, etc.)
   • The data it represents
   • Key trends or insights
4. Keep descriptions concise but informative

Example Chart Alt Text:

Poor: "Chart"

Better: "Bar chart showing quarterly sales"

Best: "Bar chart showing Q1-Q4 sales in millions: Q1: $2.1M, Q2: $2.4M, Q3: $2.8M, Q4: $3.1M. Sales increased 47% throughout the year."

XLSX-01-002: Image Missing Alternative Text {#XLSX-01-002}

What's Wrong: An image in the workbook has no alternative text.

Impact: Critical - Image content is inaccessible.

How to Fix:

1. Click on the image
2. Right-click and select Edit Alt Text
3. Enter a description of the image
4. If decorative, check Mark as decorative

When Images Need Alt Text:

• Company logos (first occurrence)
• Product images
• Screenshots with important information
• Icons that convey meaning

When to Mark as Decorative:

• Decorative borders
• Background images
• Repeated logos

XLSX-01-003: Alternative Text Is Empty or Inadequate {#XLSX-01-003}

What's Wrong: An image or chart has an alt text field, but it's empty or contains generic text that doesn't describe the content.

Impact: Critical - Users receive no meaningful information.

Common Inadequate Alt Text:

• Empty or whitespace only
• "Image" or "Picture"
• The filename ("chart1.png")
• "Chart" without data description

How to Fix:

1. Click on the element
2. Right-click and select Edit Alt Text
3. Replace empty or generic text with specific descriptions
4. For charts, include the key data points or trends

XLSX-01-004: SmartArt or Diagram Missing Alternative Text {#XLSX-01-004}

What's Wrong: A SmartArt graphic or diagram doesn't have alternative text describing its content and relationships.

Impact: Serious - Complex information structures are inaccessible.

How to Fix:

1. Click on the SmartArt or diagram
2. Right-click and select Edit Alt Text
3. Describe:
   • The type of diagram (org chart, process flow, etc.)
   • The key elements and relationships
   • The overall meaning

Example SmartArt Alt Text: "Process flow diagram showing three steps: 1. Submit Request, 2. Manager Review, 3. Approval/Rejection. Arrows indicate sequential flow."

Writing Effective Alt Text for Charts

Include Key Information:

1. Chart type - Bar, line, pie, scatter, etc.
2. What it shows - Sales data, survey results, etc.
3. Key insights - Trends, comparisons, outliers
4. Specific data - Important values or percentages

Keep It Concise:

• Aim for 1-2 sentences for simple charts
• Complex charts may need more detail
• Don't repeat information that's already in the sheet

Consider the Context:

• What's the chart's purpose in the workbook?
• What conclusions should readers draw?
• What data would readers need to understand the point?

Using Microsoft's Accessibility Checker

Excel's Accessibility Checker finds most alt text issues:

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

Data Tables as Alternatives

For complex charts, consider providing data tables:

1. Include the source data in a clearly labeled range
2. Reference the data table in the chart's alt text
3. Format the data table accessibly (with headers)

Example: "Bar chart of quarterly sales. See cells A1:B5 for complete data."

Best Practices

Do:

• Describe chart data and insights, not just appearance
• Include trend information ("Sales increased 25%")
• Note the most important data points
• Provide data table references for complex charts

Don't:

• Use "Chart of..." or "Image of..." (screen readers announce the type)
• Include the word "alt text" in your description
• Write overly long descriptions
• Describe decorative elements

Additional Resources

• Microsoft: Add alternative text to a shape, chart, or SmartArt
• W3C WCAG 1.1.1 Non-text Content
• WebAIM: Accessible Data Tables