What is AsciiDoc?

AsciiDoc tables are delimited by |=== and take a cols attribute describing the columns.

Who uses it

Antora documentation sites, and technical writing teams that outgrew Markdown.

Writing AsciiDoc

The header option is set so the first row renders as a header row rather than data.

What it can hold

AsciiDoc is a markup language. Cells are introduced by a pipe and may carry their own formatting or another table. A machine can read it back, but only by following the conventions rather than a rule the format enforces.

It keeps

Nested values. A cell can hold a list or an object rather than only a single value.
A line break inside a cell, which survives rather than ending the row.
Presentation - weight, alignment, colour and widths - alongside the values themselves.
A header that is marked as one, rather than being the first row by convention.

It cannot express

Types. Every value is text. A column of digits is indistinguishable from a column of numbers until something downstream decides to read it as one, which is where a leading zero usually disappears.
A null. An absent value and an empty one look the same, and nothing in the file says which was meant.

What it looks like

Example AsciiDoc

[cols="1,1,1,1,1",options="header"]
|===
| id | name | role | started | hours
| 007 | Halima Yusuf | Analyst, data | 2024-03-15 | 38.5
| 012 | Jonah "Jo" Pryce | Engineer | 2025-11-02 | 
| 104 | Wei Chen | Manager | 2023-06-30 | 40
|===

Questions

How do I open AsciiDoc files?

AsciiDoc is written by Tablizer rather than read by it. Open the file in whichever tool the format belongs to.

Is AsciiDoc a good format for sharing data?

It depends who is receiving it. Antora documentation sites, and technical writing teams that outgrew Markdown. If the recipient is outside that group, a plain CSV travels further than anything else.