Slack’s mrkdwn is not standard Markdown
Slack calls its formatting syntax “mrkdwn”, and it differs from standard Markdown in ways that catch almost everyone out. Bold is a single asterisk. Strikethrough is a single tilde. There are no headings, no underline, and links use an angle-bracket format. This formatter renders your text exactly as Slack will, so you stop guessing — type on the left, see a Slack-styled preview on the right, and copy it in.
The formatting Slack supports
- Bold —
*text*(single asterisk) - Italic —
_text_ Strikethrough—~text~(single tilde)Inline codeand fenced```code blocks- Blockquotes with
> - Links —
<https://example.com|link text> - Bulleted and numbered lists
Where Slack differs from Markdown
If you’re used to GitHub or standard Markdown, three things will surprise you:
- Bold is one asterisk, not two.
**text**shows the literal asterisks in Slack;*text*is bold. - Strikethrough is one tilde, not two. Use
~text~. - No headings and no underline. Reach for bold to emphasize a line, since
# Headingrenders as literal text.
The preview above applies these rules faithfully, so you can see the difference between what you’d type in Slack versus a standard Markdown editor.
Private and instant
The formatter runs entirely in your browser — nothing is uploaded. Draft your standup notes, announcements, and messages, preview them the Slack way, and copy them across when they look right.
Want the full written walkthrough, including how mrkdwn differs from standard Markdown? Read our guide: Slack Formatting: A Complete Guide to mrkdwn.
Frequently Asked Questions
How do you make text bold in Slack? +
Wrap it in single asterisks: *like this*. Unlike most Markdown, Slack uses one asterisk for bold, not two.
Why doesn't **double asterisk** work in Slack? +
Slack's mrkdwn uses single asterisks for bold. Typing **text** will literally show the asterisks. Use *text* instead — the formatter above previews it correctly.
How do you strike through text in Slack? +
Use a single tilde on each side: ~like this~. Standard Markdown uses double tildes, but Slack uses one.
How do links work in Slack formatting? +
Slack uses an angle-bracket format: <https://example.com|link text>. When you paste a plain URL into Slack it also auto-links.
Does Slack support headings or tables? +
Classic mrkdwn has no headings or tables. Use bold text for emphasis, and code blocks to keep tabular data aligned.