A command-line tool to convert Mermaid diagrams to high-resolution PNG images.

• Convert .mmd files to PNG images
• Extract and convert Mermaid diagrams from Markdown (.md) files
• High-resolution output with configurable scaling
• Multiple theme options (default, dark, forest, neutral, base, coder)
• Custom background colors (including transparent)
• Path completion for easier file selection
• Multiple diagram extraction from a single Markdown file

• Bun runtime (v1.2.17 or later)

# Clone the repository
git clone https://github.com/tadeasf/mermaid2png.git
cd mermaid2png

# Install dependencies
bun install

# Make the script executable
chmod +x ./src/index.ts

# Optional: Create a symlink to use it globally
sudo ln -s "$(pwd)/src/index.ts" /usr/local/bin/mermaid2png

# Install directly from the repository
bun install -g github:tadeasf/mermaid2png

# Or install from the local directory
cd mermaid2png
bun run install-global

# Clone the repository
git clone https://github.com/tadeasf/mermaid2png.git
cd mermaid2png

# Install dependencies
bun install

# Compile the executable
bun run compile

# The executable will be created as 'mermaid2png' in the current directory
# Move it to a directory in your PATH to use it globally
sudo mv mermaid2png /usr/local/bin/

# Convert a Mermaid file to PNG
bun run src/index.ts path/to/diagram.mmd

# Or if you installed it globally
mermaid2png path/to/diagram.mmd

mermaid2png <input-file> [output-file] [theme] [background-color] [scale] [width] [height]

• input-file: Path to a Mermaid (.mmd) or Markdown (.md) file
• output-file: (Optional) Path for the output PNG file
• theme: (Optional) Mermaid theme (default, dark, forest, neutral, base, coder)
• background-color: (Optional) Background color (white, transparent, or hex color)
• scale: (Optional) Scale factor for resolution (default: 2)
• width: (Optional) Width in pixels (default: 1920)
• height: (Optional) Height in pixels (default: 1080)

If you run the tool without arguments, it will prompt you for each parameter with helpful defaults:

bun run src/index.ts

mermaid2png flowchart.mmd

mermaid2png flowchart.mmd output.png dark transparent

mermaid2png flowchart.mmd output.png default white 4 3840 2160

mermaid2png document.md

The tool supports the following Mermaid themes:

• default: Standard light theme
• dark: Dark background theme
• forest: Green-based theme
• neutral: Balanced color theme
• base: Minimal theme
• coder: Developer-friendly theme

MIT