Which Markdown features
survive PDF export

Is the output a real document

Most comparisons stop at whether a construct renders. These are the properties that decide whether the file behaves like a document once it exists: whether a screen reader can read it, whether a reader’s sidebar shows its structure, and whether the type looks the same on someone else’s machine.

Notes on particular rows

Mermaid diagrams

Checks the label text survives, which is where clipping shows up.

A page-busting tall image stays whole

A 3000px image. Passes only if top and bottom land on one page.

Alt text reaches the PDF's structure tree

An image with no visible content is treated as decorative and is correctly left out of the structure tree; this probe uses a visible one.

Two currency amounts in one sentence

Two dollar signs are read as inline maths by many renderers, which collapses the prose between them.

GitHub alert boxes ([!NOTE])

A GitHub extension. The text survives as a block quote; the coloured box is GitHub's own styling.

Obsidian wikilinks become working links

A wikilink resolves against a vault, so nothing can turn it into a working link once the text has left. Both converters pass the words through; neither produces a link. Rewrite the ones readers need to follow.

Definition lists

A pandoc extension rather than GitHub-flavoured Markdown.

Pandoc superscript and subscript (x^2^)

Pandoc's own syntax. GitHub-flavoured Markdown has no equivalent; use <sub> and <sup>.

Emoji shortcodes (:rocket:)

GitHub renders these server-side. Neither converter expands them; paste the emoji itself.

Mermaid inside a table cell

Markdown tables cannot contain a fenced block at all, so no converter can render this. Keep diagrams at the top level.

A table wider than the page

Fourteen columns on A4. Passes only if the last column is still in the text layer rather than off the page edge.

Headings to six levels

All six render. The sixth level is set in uppercase by the stylesheet, so its glyphs differ from the source while the text is unchanged.

Abbreviation definitions

Another pandoc extension with no GitHub-flavoured equivalent.

Obsidian transclusions expand into the note

A transclusion embeds another note live inside Obsidian. Nothing can resolve that reference once the text leaves the vault, so the content is never pulled in. Paste it by hand if it needs to appear.

How this was measured

Each construct is a small Markdown document converted through each tool. The resulting PDF is then inspected rather than eyeballed: pdftotext for whether the content reached the text layer and whether raw syntax leaked through unrendered, pdfinfo for tagging and page count, pdffonts for font embedding, and the raw file for link annotations and the outline tree. A construct counts as surviving only when its content appears and no unrendered syntax is left behind.

• Pandoc was pandoc 3.12.1, rendering through the typst engine. A different engine gives different results, particularly for raw HTML and diagrams
• The VS Code extensions and Obsidian's own export are absent rather than guessed at. Neither can be driven headlessly from this harness, and filling the columns in from their documentation would not be a measurement
• A page-busting case is included on purpose: the tall-image row uses a 3000px image, which is taller than a page and is where break-inside stops helping
• The probe is in the repository as scripts/feature-matrix.mts and writes the data file this page reads, so the numbers cannot drift from the page

The converter these measurements describe is a free Markdown to PDF converter, with no account and no watermark.