Markdown Formatter
Normalize full-width to half-width, fix spacing. Format HackMD-compatible Markdown.
Input
Formatted
Formatting rules
- Full→half: ＃→#, －→-, ０-９→0-9, ［］→[], （）→() etc.
- Headers:
##text→## text - Lists:
-item→- item,1.item→1. item - Blockquotes:
>text→> text,さらに> 引用→さらに > 引用 - List indent: Leading full-width space → 2 half-width spaces
- :::details: Add space between
:::detailsand title - Tables:
|a|b|→| a | b | - Footnotes:
[^1]:content→[^1]: content - Horizontal rules:
***/___→--- - Zenn image:
→ - Preserved: Code blocks, math ($$/$...$),
\*...\*/\[...\], links/images,:::message/:::details/:::note,<details>/<!-- -->/@[card]etc. - In-text #: Only heading # at line start is half-width; mid-sentence # preserved
Supported Services
Compatible with Markdown syntax used by the following services. Also works with many others (GitHub, GitLab, HackMD, Obsidian, etc.).
Zenn ▼
Supported syntax:
- Headings, lists, blockquotes, tables, footnotes, horizontal rules
- Images:
width, caption*text* - Code:
lang:filename,diff js - Math:
$$block,$inline (KaTeX) - Custom:
:::message/:::message alert/:::details(nest with:::) - Embeds:
@[card]@[tweet]@[youtube]@[gist]etc. - mermaid, emoji
:emoji:, HTML comment<!-- -->
Qiita ▼
Supported syntax:
- GFM + extensions. Code:
lang:filename,diff_lang :::note info/warn/alert<details><summary>collapsible- Checkbox
- [ ]- [x], description list<dl> - Math:
```mathor$`...`$ - PlantUML, Mermaid, emoji, link cards (URL-only line)
- Reference links
[text][ref], anchor#heading
note ▼
Supported syntax:
- Headings, blockquotes, lists, emphasis, code blocks, strikethrough, horizontal rules
- Headings: h2, h3 only (h1→h2)
- Emphasis:
**preferred (__needs spaces) - Lists: avoid mixing
-and*
VSCode / GFM ▼
Supported syntax:
- Headings, lists, blockquotes, links, images, tables, horizontal rules
- Code:
lang:filename(e.g.c:main.c) - Italic
*, bold**, strikethrough~~
Zenn, Qiita, note, HackMD, GitHub, GFM and more.
Usage
Enter Markdown to format. Full-width #→half-width, ##text→## text, -item→- item. Code blocks preserved.
When to use
Fix messy Markdown from copy-paste, format before using in HackMD.
Examples
#heading→# heading, ##text→## text, -item→- item