🧰Locly

Preview Markdown & Mermaid Diagrams

Live Markdown preview with GFM and Mermaid diagrams

Supports GFM and ```mermaid code blocks. Diagrams render locally — nothing is uploaded.

About This Tool

Markdown Preview shows a live split view of Markdown with GitHub-flavored Markdown (GFM). Fenced ```mermaid blocks render as flowcharts, sequence diagrams, and more using Mermaid in your browser. You can copy HTML or print. Everything is processed locally in your browser — drafts never leave your device.

How to Use

  1. Paste or type Markdown on the left
  2. See the live preview on the right
  3. Add a ```mermaid block for diagrams
  4. Copy HTML or print if needed
  5. Clear to start over

Common Use Cases

  • Draft README files
  • Document architecture with Mermaid
  • Prepare blog posts
  • Share printable notes
  • Validate GFM before publishing

FAQ

Q1: Does it support Mermaid?

Yes. Put diagram source in a ```mermaid fenced code block and it renders locally.

Q2: Is Markdown uploaded?

No. Parsing and Mermaid rendering are processed locally in your browser.

Q3: What Markdown flavor is used?

GitHub-flavored Markdown (GFM) via marked, including tables and line breaks.

Q4: What if a Mermaid diagram fails?

A friendly error appears in place of the diagram so you can fix the syntax.

Q5: Can I print the preview?

Yes. Use Print for a print-friendly layout of the preview pane.

Related Tools

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