Accessible Maps in Documents: A Practical Workflow
Today’s blog post explores accessible maps inside documents. This is a different accessibility problem from interactive web maps, so we are focusing specifically on static maps that appear in PDFs, reports, Word files, and similar documents.
With document maps, most of the work happens through alternate text, tagging, and access to the data behind the map. At the end of this post, you’ll find a clear workflow to apply to almost any map you encounter in a document.
Video Guide
A Map Is More Than a Picture
Maps inside documents usually begin as static images. You might export one from a GIS tool, capture it from a public dataset, take a screenshot, or place an existing graphic into a report.
Common examples include choropleth maps that use shading to show differences across regions, point maps that identify locations, route maps that show a path, regional maps that define service areas, and store locator maps.
The important thing to remember is that an informative map often communicates geography along with an underlying data layer. Your accessible version needs to give the reader access to the information the map conveys.
Start with one question: Is the map decorative or informative?
That decision drives the rest of your accessibility work. If the map simply adds visual interest, you can mark it as decorative or as an artifact, depending on the application you are using.
If the map communicates meaningful information, keep going.
Why Generic Alt Text Fails
Imagine a county health report with a map that shows uninsured rates across different regions. A screen reader user reaches the map and hears only the word “map.”
The reader now knows that a graphic exists, but receives none of the information the graphic was designed to communicate. The differences between regions disappear from the experience.
A low vision reader may face a different barrier. They might see the map but struggle to distinguish similar colors or shaded regions in the legend.
A structured data table can help both readers. It gives them direct access to the same values shown visually on the map.
Write Alt Text for the Main Takeaway
For an informative map, write concise alternate text that explains its purpose and communicates its most important finding. Focus on the insight the reader should understand first.
For example:
“Regional uninsured rate map for 2025. South region has the highest rate at 21 percent, while East region has the lowest rate at 6 percent. Detailed values appear in the table below.”
This gives the reader the central message immediately. It also points them toward a structured source for the detailed values.
For more complex maps, keep the short alternative focused on the main takeaway and provide the detailed information elsewhere, such as nearby text, a longer description, or a structured data table.
Avoid using alt text such as “map,” “county map,” or “regional map” when the image communicates meaningful data. Those labels identify the image type but leave out its purpose.
Use a Data Table for Complex Maps
Complex maps can contain many regions and values. Trying to describe every value in a long block of alt text can make the information difficult to follow.
A structured table often serves the reader better. Put each location and its corresponding value into real, selectable text, then mark up the table properly so a screen reader can move through it by row and column.
For example:
Regional Uninsured Rates, 2025
| Region | Uninsured Rate |
|---|---|
| South | 21% |
| West | 15% |
| North | 10% |
| Central | 8% |
| East | 6% |
This approach allows readers to inspect individual values and compare regions at their own pace. It also keeps the map’s alt text focused on the main takeaway instead of turning it into a long verbal data dump.
Tag the Map Correctly
In a tagged PDF, identify an informative map as a Figure. This places the map within the document’s accessible structure.
Make sure the reader can also reach important information from the legend and labels. You can include that content in the document’s reading order or incorporate the necessary information into the map description.
If the map sits outside the tag tree or appears only as a background image, assistive technology may skip it entirely. Proper tagging helps ensure that the map is available to assistive technology as meaningful content.
Do More Than Color
Maps often use color to separate regions or show differences in values. A red and green map might look obvious to some readers while creating serious problems for people with color vision deficiencies or reduced vision.
Add another way to communicate the distinction. Direct labels and printed values work especially well because they identify the region and provide the data at the same time.
You can also choose a color scale that provides clear tonal differences and sufficient contrast. The goal is to make the map understandable without requiring the reader to distinguish specific colors.
Check Contrast on Meaningful Elements
Map labels need enough contrast against their backgrounds to remain readable. Boundaries and other graphical elements that carry meaning also need to remain distinguishable.
A visually polished map can still create accessibility barriers if labels disappear into the background or important shapes become difficult to perceive. Check the finished map at the size and quality that readers will actually encounter in the document.
A Five-Step Workflow for Accessible Maps
You can use the same basic process whenever you encounter a map in a document.
- Decide whether the map is decorative or informative. Mark a decorative map as an artifact or decorative element. Continue the remediation process when the map communicates information.
- Write alternate text that states the main takeaway. Tell the reader what the map shows and identify the most important result.
- Provide detailed data in an accessible format when needed. Use a properly structured data table or clear text labels when the map contains values that readers need to examine.
- Tag the map as a Figure and make supporting information accessible. Include legends and relevant labels in the reading order or provide their information through the map description.
- Test the document with a screen reader. Confirm that a nonvisual reader can identify the map’s purpose and reach the information it communicates.
The companion video walks through a live example.
WCAG Requirements That Apply to Document Maps
Several WCAG success criteria apply to maps in documents and help guide how you present the map, its data, and its visual information:
- WCAG 1.1.1, Non-text Content: Provide a text alternative that communicates the map’s meaningful information, not just the fact that a map is present.
- WCAG 1.3.1, Info and Relationships: Preserve the structure of supporting information. For example, use a properly marked-up table so assistive technology can identify relationships between headers and data cells.
- WCAG 1.4.1, Use of Color: Do not rely on color alone to distinguish regions or communicate values. Add labels, values, or another visual cue.
- WCAG 1.4.3, Contrast Minimum: Make sure map labels and other text have enough contrast against their backgrounds to remain readable.
- WCAG 1.4.11, Non-text Contrast: Provide sufficient contrast for meaningful graphical elements such as boundaries, symbols, and other visual features that convey information.
Make the Map's Meaning Accessible
When making a map accessible, focus on what the reader needs to understand from it. Ask what information someone would miss without seeing the map, then provide that information through accessible text, document structure, or a structured data equivalent.
A simple map may only need meaningful alt text that captures its purpose and main takeaway. A map with multiple locations or values will usually benefit from a structured table that lets readers review the underlying data directly.
The goal is to give readers access to the same geographic information and data the map was created to communicate. When the accessible version preserves that meaning, the map can serve readers regardless of how they access the document.
Let me be your champion for inclusion. I offer tailored solutions (and self-paced courses!) to ensure your documents meet and exceed compliance expectations. For more detailed insights, tutorials, and in-depth discussions on accessibility and related topics, don’t forget to check out my YouTube channel: The Accessibility Guy on YouTube. Subscribe for regular updates!
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