Top 10 Best Mermaid Editor Software of 2026

Miro supports Mermaid diagram types including flowcharts, sequence diagrams, class diagrams, ER diagrams, cloud diagrams, and state diagrams. Teams can paste existing code into a board, start from a template, or use an MCP client such as Claude Code or Cursor to work with diagrams alongside the team.

A key tradeoff is that Miro places Mermaid diagrams in a collaborative canvas workflow rather than focusing solely on a local code-editor preview. This suits an engineering team reviewing a system flow with product or business stakeholders, who can comment on and adjust the visual diagram together while preserving Mermaid as portable source.

Obsidian stores notes as local Markdown files and renders Mermaid code blocks for flowcharts, sequence diagrams, and other supported diagram types. The diagrams remain editable as text within the note, and community plugins can extend workflows through Obsidian's JavaScript plugin API.

The main limitation is the lack of a native visual editor for placing nodes or routing connectors, so authors need to know Mermaid syntax. That model suits engineers maintaining architecture diagrams alongside project notes, but teams needing shared canvas editing or centralized governance will need another workflow.

Eraser combines a Mermaid editor and rendered preview with a broader workspace for diagrams and engineering documentation. Teams can use Mermaid alongside other diagram types, then organize diagrams and docs in shared workspaces.

That broader workspace adds interface overhead for users who only need quick Mermaid edits. It suits engineering teams that want to maintain sequence or flow diagrams beside the technical documentation those diagrams explain.

Among browser-based diagram editors, Excalidraw pairs a hand-drawn canvas with a Mermaid-to-Excalidraw conversion workflow. It converts Mermaid text into editable canvas elements for rearranging, annotation, and PNG or SVG export.

Visual Studio Code edits Mermaid diagrams as text and renders Mermaid code fences in its Markdown preview. Its distinction is a general-purpose code editor with an extension API, rather than a dedicated diagram canvas.

CodePen suits developers who want to prototype Mermaid diagrams inside a browser-based HTML, CSS, and JavaScript workspace. Its live preview can render Mermaid diagrams after the library is added to a Pen, and saved Pens can be embedded in documentation or shared for feedback. CodePen does not provide a dedicated Mermaid editor, diagram controls, or a Mermaid-specific export workflow.

Unlike dedicated diagram editors, Typora keeps Mermaid source in Markdown and renders diagrams inline with the surrounding text. Writers create diagrams in fenced code blocks, then edit the Mermaid syntax directly in the document.

Mermaid Chart pairs Mermaid's text syntax with a browser-based visual editor, so users can build diagrams through code or canvas editing. It supports flowcharts, sequence diagrams, class and entity-relationship diagrams, state diagrams, and Gantt charts.

diagrams.net converts Mermaid source into diagrams on a general-purpose canvas, where those results can sit beside manually placed shapes and connectors. Its Mermaid insertion dialog accepts code and supports editing the source after insertion, while the canvas adds annotations, layout controls, and SVG, PNG, and PDF export.

HackMD suits engineering teams that keep design documents and diagrams in Markdown, rendering Mermaid code blocks directly in the note preview. Its browser editor supports real-time coediting and shareable notes, while team workspaces organize collaborative documentation.