Mermaid code

Tip: Ctrl + Enter to generate

Preview

Choose a sample or write Mermaid code, then generate.

Theme

Plain Academic Pastel Brutalism NeoBrutalism Ocean Forest Sunset Custom

Colors

Primary #DDEBFF Secondary #D1FAE5 Accent #FCE7F3 Text #1F2937 Lines #334155

Line thickness

1.5 px

Background

Transparent White Custom

#FFFFFF

Advanced CSS

Applied through Mermaid’s themeCSS. Remote URLs are blocked.

AI readjustment Highly experimental

AI can change diagram meaning or return invalid Mermaid. Review the code and preview after every adjustment.

Gemini API key Saved encrypted in this app's SQLite database

Checking…

Paste a raw AQ./AIza key or its environment-variable assignment. The saved key is never returned to the browser.

Adjust the current diagram

Save a Gemini API key to enable the presets.

Gemini 3.5 Flash-Lite • preset prompts only

Save options Store this setup in local SQLite