Martian: Markdown to Notion Parser

Convert Markdown and GitHub Flavoured Markdown to Notion API Blocks and RichText.

Martian is a Markdown parser to convert any Markdown content to Notion API block or RichText objects. It uses unified to create a Markdown AST, then converts the AST into Notion objects.

Designed to make using the Notion SDK and API easier. Notion API version 1.0.

Supported Markdown Elements

All inline elements (italics, bold, strikethrough, inline code, hyperlinks, equations)
Lists (ordered, unordered, checkboxes) - to any level of depth
All headers (header levels >= 3 are treated as header level 3)
Code blocks, with language highlighting support
Block quotes
- Supports GFM alerts (e.g. [!NOTE], [!TIP], [!IMPORTANT], [!WARNING], [!CAUTION])
- Supports Notion callouts when blockquote starts with an emoji (optional, enabled with enableEmojiCallouts)
- Automatically maps common emojis and alert types to appropriate background colors
- Preserves formatting and nested blocks within callouts
Tables
Equations
Images
- Inline images are extracted from the paragraph and added afterwards (as these are not supported in notion)
- Image urls are validated, if they are not valid as per the Notion external spec, they will be inserted as text for you to fix manually

Usage

Basic usage:

The package exports two functions, which you can import like this:

// JS
const {markdownToBlocks, markdownToRichText} = require('@tryfabric/martian');
// TS
import {markdownToBlocks, markdownToRichText} from '@tryfabric/martian';

Here are couple of examples with both of them:

markdownToRichText(`**Hello _world_**`);

<details> <summary>Result</summary> <pre> [ { "type": "text", "annotations": { "bold": true, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" }, "text": { "content": "Hello " } }, { "type": "text", "annotations": { "bold": true, "strikethrough": false, "underline": false, "italic": true, "code": false, "color": "default" }, "text": { "content": "world" } } ] </pre> </details>

markdownToBlocks(`
hello _world_ 
*** 
## heading2
* [x] todo

> 📘 **Note:** Important _information_

> Some other blockquote
`);

<details> <summary>Result</summary> <pre> [ { "object": "block", "type": "paragraph", "paragraph": { "rich_text": [ { "type": "text", "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" }, "text": { "content": "hello " } }, { "type": "text", "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": true, "code": false, "color": "default" }, "text": { "content": "world" } } ] } }, { "object": "block", "type": "divider", "divider": {} }, { "object": "block", "type": "heading_2", "heading_2": { "rich_text": [ { "type": "text", "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" }, "text": { "content": "heading2" } } ] } }, { "object": "block", "type": "to_do", "to_do": { "rich_text": [ { "type": "text", "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" }, "text": { "content": "todo" } } ], "checked": true } }, { "type": "callout", "callout": { "rich_text": [ { "type": "text", "text": { "content": "Note:" }, "annotations": { "bold": true, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" } }, { "type": "text", "text": { "content": " Important " } }, { "type": "text", "text": { "content": "information" }, "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": true, "code": false, "color": "default" } } ], "icon": { "type": "emoji", "emoji": "📘" }, "color": "blue_background" } }, { "type": "quote", "quote": { "rich_text": [ { "type": "text", "text": { "content": "Some other blockquote" }, "annotations": { "bold": false, "strikethrough": false, "underline": false, "italic": false, "code": false, "color": "default" } } ] } } ] </pre> </details>

Working with blockquotes

Martian supports three types of blockquotes:

Standard blockquotes:

> This is a regular blockquote
> It can span multiple lines

GFM alerts (based on GFM Alerts):

> [!NOTE]
> Important information that users should know

> [!WARNING]
> Critical information that needs attention

Emoji-style callouts (optional) (based on ReadMe's markdown callouts):

> 📘 **Note:** This is a callout with a blue background
> It supports all markdown formatting and can span multiple lines

> ❗ **Warning:** This is a callout with a red background
> Perfect for important warnings

GFM Alerts

GFM alerts are automatically converted to Notion callouts with appropriate icons and colors:

NOTE (📘, blue): Useful information that users should know
TIP (💡, green): Helpful advice for doing things better
IMPORTANT (☝️, purple): Key information users need to know
WARNING (⚠️, yellow): Urgent info that needs immediate attention
CAUTION (❗, red): Advises about risks or negative outcomes

Emoji-style Callouts

By default, emoji-style callouts are disabled. You can enable them using the enableEmojiCallouts option:

const options = {
  enableEmojiCallouts: true,
};

When enabled, callouts are detected when a blockquote starts with an emoji. The emoji determines the callout's background color. The current supported color mappings are:

📘 (blue): Perfect for notes and information
👍 (green): Success messages and tips
❗ (red): Warnings and important notices
🚧 (yellow): Work in progress or caution notices

All other emojis will have a default background color. The supported emoji color mappings can be expanded easily if needed.

If a blockquote doesn't match either GFM alert syntax or emoji-style callout syntax (when enabled), it will be rendered as a Notion quote block.

Examples

Standard blockquote:

markdownToBlocks('> A regular blockquote');

<details> <summary>Result</summary> <pre> [ { "object": "block", "type": "quote", "quote": { "rich_text": [ { "type": "text", "text": { "content": "A regular blockquote" } } ] } } ] </pre> </details>

GFM alert:

markdownToBlocks('> [!NOTE]\n> Important information');

<details> <summary>Result</summary> <pre> [ { "object": "block", "type": "callout", "callout": { "rich_text": [ { "type": "text", "text": { "content": "Note" } } ], "icon": { "type": "emoji", "emoji": "ℹ️" }, "color": "blue_background", "children": [ { "type": "paragraph", "paragraph": { "rich_text": [ { "type": "text", "text": { "content": "Important information" } } ] } } ] } } ] </pre> </details>

Emoji-style callout (with enableEmojiCallouts: true):

markdownToBlocks('> 📘 Note: Important information', {
  enableEmojiCallouts: true,
});

<details> <summary>Result</summary> <pre> [ { "object": "block", "type": "callout", "callout": { "rich_text": [ { "type": "text", "text": { "content": "Note: Important information" } } ], "icon": { "type": "emoji", "emoji": "📘" }, "color": "blue_background" } } ] </pre> </details>

Working with Notion's limits

Sometimes a Markdown input would result in an output that would be rejected by the Notion API: here are some options to deal with that.

An item exceeds the children or character limit

By default, the package will try to resol

Martian

Install / Use

README