Summaries for tables

Silktide looks for data tables that carry no summary describing their purpose and structure. A summary gives people who cannot see the table an overview before they start reading it, so they know what to expect and how it is organized.

This is an assisted check: Silktide cannot judge whether a particular table is complex enough to need a summary, so it reports candidates for you to review.

Why this matters

A sighted reader glances at a table and immediately grasps its shape - how many columns, what they contain, where to look. A user gets none of that: the table is read one cell at a time, and for a complex table it can take real effort just to work out how it is organized. A short description up front - "quarters in columns, product lines in rows" - saves that effort and lets the listener decide whether the table is worth exploring at all.

Simple tables rarely need this; complex ones benefit greatly.

How to fix it

Decide whether the table's structure needs explaining. A small table with one clear heading row usually doesn't; a table with merged cells, several heading levels, or abbreviations usually does.
If it does, add a summary attribute describing how the table is organized - not repeating its title:

<!-- The summary explains structure, the caption gives the title -->
<table summary="Quarters in columns, product lines in rows; all amounts in US dollars">
  <caption>2026 sales</caption>
  ...
</table>

If the table is simple and self-explanatory, no change is needed - you can the finding.

How Silktide tests this

Find every table on each page.
Skip tables marked as presentational with role="presentation".
Skip tables with only one row or only one column, which are unlikely to be data tables.
Report each remaining table whose summary attribute is missing or empty, for you to review.

Troubleshooting

Isn't the summary attribute obsolete?

Yes - summary comes from HTML 4 and is obsolete in current , though screen readers still announce it. If you prefer modern alternatives, a visible paragraph before the table or a description linked with aria-describedby works for more users. Note that this check only detects the summary attribute itself, so a table described another way will still be reported - approve the finding in that case.

The summary repeats my caption

A summary that just duplicates the visible caption adds nothing and is reported by a separate check - see Identical table summary and caption.