Slack Message Formatting with mrkdwn
Slack’s text formatting looks like Markdown but is its own dialect called mrkdwn. If you have ever had `**bold**` show up literally in Slack, this is why.
mrkdwn is not Markdown
Bold is *single asterisks*, italic is _underscores_, strikethrough is ~tildes~, and links are <https://url|label>. There is no heading or list syntax the way Markdown has. The Slack Message Formatter previews it live so you can paste with confidence.
When to use Block Kit
For anything beyond a paragraph, sections, buttons, images, dividers, Slack uses Block Kit, a JSON layout format. Assemble it visually with the Slack Block Kit Builder. A single message allows up to 50 blocks.
Sending via webhooks
Incoming webhooks accept a JSON payload with text or a blocks array. Build the payload and a ready curl command with the Slack Webhook Sender.
Try the tools
All guides →Slack Message Formatter
Format Slack messages with mrkdwn (bold, italic, code, quotes, links) with a live preview.
Launch tool →Slack Block Kit Builder
Assemble Slack Block Kit message JSON for webhooks and chat.postMessage.
Launch tool →Slack Webhook Sender
Build the JSON payload and curl command for any Slack incoming webhook, with Block Kit support.
Launch tool →