Markdown Callout / Admonition Builder (GitHub, Obsidian)

GitHub introduced callout syntax in 2023: > [!NOTE], > [!WARNING], etc. Obsidian, MkDocs, Docusaurus all support similar formats. This builder generates the correct syntax for each platform.

Markdown

Rendered (GitHub-style)

How to use the Markdown Callout / Admonition Builder (GitHub, Obsidian)

Choose the platform style and callout type, add an optional title and body content, and copy the generated Markdown. The preview shows roughly how it renders. Each platform uses a different syntax for the same idea, so pick the one your docs target.

Callout syntax across platforms

A callout (also called an admonition) is a highlighted block — a note, tip, warning, or caution — that stands out from body text. GitHub added native support in 2023 with the > [!NOTE] blockquote syntax, rendering a coloured box with an icon. The trouble is that every documentation platform invented its own spelling for the same feature before any standard existed.

Obsidian uses a similar blockquote form, Docusaurus wraps the block in :::note fences, and MkDocs Material writes !!! note with indented content. This builder generates the correct syntax for whichever platform you target, so you do not have to remember four dialects. Pick the style and type, write your content, and copy the result.

Common use cases

  • GitHub READMEs — add a native [!WARNING] or [!TIP] box to a repo doc.
  • Docusaurus sites — generate the :::note fenced admonition Docusaurus expects.
  • MkDocs Material — produce the !!! note block with correctly indented content.
  • Obsidian notes — build a callout for a personal knowledge base.
  • Porting docs — re-emit the same callout in another platform's syntax when migrating.

Frequently asked questions

Why do GitHub, Obsidian, and MkDocs use different callout syntax?
Each adopted admonitions before any common standard existed, so they diverged. GitHub uses > [!NOTE], MkDocs uses !!! note, Docusaurus uses :::note. The concept is the same; only the markup differs.

Which callout types does GitHub support?
GitHub recognizes five: Note, Tip, Important, Warning, and Caution. Other platforms add their own such as Info or Danger, which is why the type list here is broader than any single platform.

Will a GitHub callout render on other sites?
Not as a callout. On a renderer that does not understand [!NOTE] it shows as an ordinary blockquote with the literal [!NOTE] text. Generate the syntax that matches where the file will be read.

Can callouts contain formatting?
Yes. The body accepts normal Markdown — bold, italic, code, links, and usually lists — though deeply nested content behaves differently per platform. Keep it simple for the most consistent rendering.
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