The Complete Markdown Cheat Sheet (With Copy-Paste Examples)
著者: Salty Deprecated Software Engineer
この記事はAIの支援を受けて作成され、正確性と品質についてチームが審査しました。すべての技術情報と例は検証済みです。
Markdown is the formatting language behind GitHub READMEs, Notion pages, Slack messages, Discord, Reddit, and most documentation sites. It's also what ChatGPT and Claude output by default. If you work in tech in 2026, you use Markdown whether you know it or not.
This cheat sheet covers everything you need. Bookmark it.
Headings
# Heading 1
## Heading 2
### Heading 3
#### Heading 4
More #s = smaller heading. Use H1 for titles, H2 for sections, H3 for subsections.
Text Formatting
**bold text**
*italic text*
***bold and italic***
~~strikethrough~~
`inline code`
> This is a blockquote
Links & Images
[Link text](https://example.com)
[Link with title](https://example.com "Hover text")
The ! before brackets makes it an image instead of a link.
Lists
- Item one
- Item two
- Nested item
1. First
2. Second
3. Third
- [x] Completed task
- [ ] Pending task
Code Blocks
Use `backticks` for inline code
```javascript
function hello() {
console.log("Hello!");
}
```
Replace "javascript" with python, bash, sql, css, etc. for proper highlighting.
Tables
| Column 1 | Column 2 | Column 3 |
|----------|----------|----------|
| Row 1 | Data | Data |
| Row 2 | Data | Data |
| Left | Center | Right |
|:-----|:------:|------:|
Colons in the separator row control text alignment.
Horizontal Rules, Footnotes & More
---
Here is a statement[^1].
[^1]: This is the footnote text.
<details>
<summary>Click to expand</summary>
Hidden content here.
</details>
Where Markdown Works
| Platform | Supports |
|---|---|
| GitHub | Full GFM (tables, task lists, footnotes) |
| Notion | Most syntax (paste Markdown, auto-converts) |
| Slack | Partial (bold, italic, code, links, lists) |
| Discord | Most syntax (no tables) |
| Full Markdown in old editor | |
| ChatGPT/Claude | Full — all output is Markdown |
Need to format text quickly? Try our free Text Tools Suite for case conversion, word count, and more.
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