Free online MMD to PDF converter

The .mmd extension identifies different file types, and this page handles both Mermaid diagrams and MultiMarkdown documents. Convert either one when a program, printer, submission system, or recipient requires a fixed-layout PDF instead of editable source text.

How to tell which MMD file you have

Both supported variants are normally plain-text files, not binary documents. Open a copy in a text editor and inspect its first lines and content:

• Mermaid diagram: commonly starts with flowchart TD, graph LR, sequenceDiagram, classDiagram, or stateDiagram-v2. It contains nodes, connectors, diagram directives, and sometimes references to images or stylesheets. Mermaid-compatible editors, documentation systems, and developer tools create these files.
• MultiMarkdown document: contains prose with Markdown headings, lists, links, tables, footnotes, citations, definition lists, or code blocks. It may begin with metadata such as Title:, Author:, or Date:. MultiMarkdown editors and text-based writing workflows create these files.

Neither variant has a universal binary header. Unreadable binary data usually indicates another format that happens to use the .mmd extension. Renaming an extension does not convert the file.

Mermaid diagram to PDF

A Mermaid .mmd file is diagram source code, not a finished image. Conversion parses the Mermaid syntax, calculates the layout, renders the nodes and connectors, and places the result on PDF pages.

For local, repeatable conversion, install Mermaid CLI and run:

mmdc -i diagram.mmd -o diagram.pdf

Mermaid CLI uses a Chromium-based browser renderer, so its installation also needs a compatible Chromium or Puppeteer environment. Options such as -t dark for the theme, -b white for the background, and -p puppeteer-config.json for browser settings control rendering.

Validate the Mermaid source before conversion and make referenced images, fonts, and other assets available to the renderer. Large diagrams can become unreadable when scaled to a page; use a larger page size, adjust the layout, or split the diagram into multiple files. Inspect connector positions, text size, and clipped edges in the resulting PDF.

MultiMarkdown document to PDF

MultiMarkdown extends Markdown with features including metadata, tables, footnotes, citations, definition lists, and cross-references. The source remains text-based, but producing a paginated PDF requires an HTML, TeX, or other document-layout renderer.

For a local HTML workflow, use the MultiMarkdown command-line processor:

multimarkdown document.mmd > document.html

Open the HTML file in a browser and select Print → Save as PDF. A stylesheet can control fonts, margins, page size, tables, code blocks, and page breaks. For automated output, Pandoc can process Markdown and some MultiMarkdown-compatible syntax:

pandoc document.mmd -o document.pdf

Pandoc's direct PDF output normally requires a TeX engine such as XeLaTeX or LuaLaTeX. MultiMarkdown-specific syntax may not render identically in Pandoc, so the HTML workflow is safer when the source uses specialized metadata, citations, or extensions. Check footnotes, tables, links, code blocks, metadata, and page breaks after conversion.

PDF format

PDF stores a paginated representation with defined page dimensions, typography, vector graphics, and print layout. It is suited to sharing, printing, submitting, and archiving rendered content when recipients do not need to edit the original .mmd source.

How to convert MMD files to PDF

1. Open a copy of the file in a text editor and identify its syntax. Mermaid diagram source contains diagram declarations and relationships; MultiMarkdown contains prose and Markdown constructs.
2. On 101convert.com, set the converter switch to Mermaid diagram or MultiMarkdown document, upload the .mmd file, and start the conversion. The service can convert the file for free without installing software.
3. Download the generated PDF and review every page. For Mermaid, check layout, connector routing, assets, and readability. For MultiMarkdown, check page breaks, tables, footnotes, metadata, code blocks, and links.

Use the local tools instead when the source is confidential, conversion must be scripted, or you need exact control over CSS, fonts, page dimensions, margins, or Mermaid's browser renderer.