To export Markdown with Mermaid diagrams to PDF, paste your Markdown — including the ```mermaid code blocks — into the converter and export. The diagrams render as sharp vector graphics in the PDF rather than being left as raw code, which is where most generic converters fall short.

Mermaid lets you write diagrams as text inside a fenced code block, so they live right next to your prose in version control. The challenge is the final step: many Markdown-to-PDF tools either print the diagram source verbatim or rasterize it into a blurry image. Rendering it properly as vector output keeps the diagram crisp at any zoom and at print resolution.

Mermaid rendering is a premium feature: a document that contains Mermaid diagrams requires a paid plan, and free accounts get a 403 when they try to convert one. You can include up to 5 diagrams per document.

Diagram types that convert

The common Mermaid diagrams all export cleanly:

Flowcharts (graph TD) — process and decision trees
Sequence diagrams — request/response and interaction flows
Gantt charts — project timelines
Class and ER diagrams — data models
State diagrams — workflows and lifecycles

How to do it

Keep each diagram in a fenced block that starts with ```mermaid.
Paste the full Markdown into the converter.
Wait for the live preview to render the diagram, then check it for overflow.
Export the PDF.

Keep diagrams readable in print

Favor vertical layouts (graph TD) over wide horizontal ones so a large diagram fits the page width.
Keep node labels short — long labels force the diagram wider than the page.
Split very large diagrams into two smaller ones rather than shrinking a single diagram until the text is unreadable.

Because the diagram is rendered as vector graphics, lines and text stay sharp in the exported PDF — suitable for documentation, technical specs, and architecture proposals that will be printed or shared at any size.