How to Make Accessible Tables in PDFs and Documents
Sighted readers connect a cell to its headers at a glance. A screen reader needs those relationships marked explicitly, or each value arrives without context.
The same table, two very different results
PDF with every cell tagged TD
| Element | Symbol | Atomic no. |
|---|---|---|
| Hydrogen | H | 1 |
Screen reader result
“Element. Symbol. Atomic number. Hydrogen. H. 1.”
The web example above uses real HTML headers so this page remains accessible; the card label describes the broken tags in the PDF being simulated.
PDF with TH header tags
| Element | Symbol | Atomic no. |
|---|---|---|
| Hydrogen | H | 1 |
Screen reader result
“Element: Hydrogen. Symbol: H. Atomic number: 1.”
In PDF structure, TH means table header and TD means table data. Scope or header associations tell assistive technology whether a header applies across a row, down a column, or to a more complex group of cells.
How to create accessible tables by format
Microsoft Word
Insert a real table, select the first row, and turn on Table Design > Header Row. In Table Properties, allow the header row to repeat across pages. Keep the grid simple, avoid blank rows or columns for spacing, and add a short caption in nearby text. Run Word's accessibility checker before exporting with document structure tags enabled.
LaTeX
Use a semantic table environment and the current tagged-PDF workflow, then inspect the result. Packages and document classes differ in how much table structure they expose. A visually correct tabular is not proof that the PDF has Table, TR, TH, and TD tags. Complex spanning cells usually need extra testing. For source syntax, see LaTeX tables and the tables tutorial.
Google Docs
Use an inserted table rather than tabs or spaces. Keep one clear header row, avoid merged cells, and describe the table's purpose in nearby text. Exported PDF tagging can vary, so confirm in the PDF Tags panel that headers are tagged as TH and associated with the correct data cells.
Fixing a PDF in Acrobat
In the Tags panel, confirm that the table contains TR rows and that header cells are TH rather than TD. Use the table editor or cell properties to set row or column scope and repair spans. Move captions outside the Table tag when appropriate, and verify the reading order by navigating cell by cell with a screen reader. The guide to PDF tags explains the surrounding structure.
Common mistakes
- Images of tables. A screenshot has no cells or headers for assistive technology. Rebuild it as a real table.
- Merged and split cells. They can break predictable grid navigation. Simplify the layout or define header and span relationships carefully.
- Layout tables. Tables used only to position content should not be announced as data tables. Use proper page layout or mark the structure as an artifact.
- Blank cells used as separators. They interrupt the data model. Use spacing and borders instead.
- Color-only meaning. Add text or symbols so a red or green fill is not the only way to identify a status.
The complete PDF accessibility workflow covers source repair, export, tagging, and testing.
Tables with math
Header tags explain where a cell sits, but they do not make an equation inside the cell understandable. Each expression still needs semantic math such as MathML or another tested alternative. Standard table tagging alone cannot provide that. Underleaf can send a short sample collection below.
Have handwritten or scanned STEM content?
Underleaf converts handwritten notes, scanned PDFs, and equations into accessible MathML, tagged PDF/UA, HTML, and clean LaTeX. Send us two or three pages for a free sample. There is no charge and no commitment.