---
title: Formatting
description: How your markdown reaches Zoom — the tokens that render, the ones Zoom cannot carry, and the structured fallback.
---

Zoom Team Chat accepts two kinds of message body: structured segments (plain text
plus a per-segment bold or italic flag), and **Markdown**, which you turn on per
message with `is_markdown_support: true`.

The adapter uses Markdown by default, because it is the only mode that can render
links, strikethrough, block quotes, and images. Markdown mode also makes Zoom
ignore the structured `style` field, so everything you want to see has to live in
the text itself.

<FormatPreview />

## What reaches Zoom

| What you write | What the adapter sends | What Zoom renders |
| --- | --- | --- |
| `**bold**` | `*bold*` | **Bold** |
| `_italic_` | `_italic_` | *Italic* |
| `` `code` `` | `` `code` `` | Monospace |
| `~strikethrough~` | `~strikethrough~` | ~~Strikethrough~~ |
| `> quote` | `> quote` | Indented, italic (Zoom's quote style) |
| `[label](https://example.com)` | `label <https://example.com>` | Label plus a clickable URL |
| `![alt](https://example.com/a.png)` | `<img:https://example.com/a.png\|alt>` | The image, if its host is trusted |
| `# Heading` | `*Heading*` | A bold line — Zoom has no heading token |
| `- item` or `* item` | `• item` | A bullet line |
| `__underline__` | `underline` | Plain text — **Zoom has no underline token** |
| A table | Pipe-separated rows, bold header | Plain text rows — **Zoom has no table token** |

Code spans and fenced blocks are protected while the rest is converted, so code
that merely looks like `~strike~` or `__underline__` is left exactly as written.
An empty message is never sent, because the Zoom API rejects empty content.

## Bold is a single asterisk

This is the one place where Zoom's documentation contradicts itself. Its chatbot
Markdown page shows `**bold**` in the syntax table but `*bold*` in the request
example. The live client follows the example:

| Token | Result |
| --- | --- |
| `*bold*` | **bold** |
| `***bold***` | **bold** |
| `_italic_` | *italic* |
| `~strike~` | ~~strike~~ |
| `**bold**` | plain text |
| `__underline__` | plain text |

So `**bold**` in your Chat SDK markdown arrives at Zoom as `*bold*`. If you write
the Zoom token directly, remember that `*text*` means emphasis in standard
Markdown, so the adapter will read it as italic. Write standard Markdown and let
the converter translate.

## Links

A markdown link keeps its label and makes the URL clickable:

```md
See [the docs](https://example.com) for more
```

arrives as `See the docs <https://example.com> for more`. Zoom documents the bare
`<url>` form; the labelled form also works in current clients.

## Images need a trusted host

The image token is sent correctly, but the Zoom client only renders images from
domains it trusts. Images from other hosts are dropped client-side, with a
`[Security] Blocked image from untrusted domain` warning in the browser console.
Add the host to your app's trusted-domain list, or use one Zoom already trusts,
such as `developers.zoom.us`.

This is a Zoom client rule. The adapter cannot override it.

## Structured fallback

Set `markdownSupport: false` (or `ZOOM_MARKDOWN_SUPPORT=false`) to send structured
segments instead:

```ts
createZoomAdapter({ markdownSupport: false });
```

That mode bolds a paragraph only when the whole paragraph is bold, including a
whole bold heading. Inline bold and italic are flattened, and links,
strikethrough, block quotes, and images keep their text but lose their
formatting. See [Configuration](/configuration) for the option and its
environment variable.

## Reading an incoming message

Incoming text is parsed with Zoom's own conventions:

| Token | Meaning |
| --- | --- |
| `__text__` | Underline, not bold |
| `~text~` | Strikethrough with a single tilde |

Everything else — `**bold**`, `_italic_`, `` `code` ``, `#` headings, `*` lists —
is standard. `message.text` holds the raw text the person typed, and
`message.formatted` holds the parsed tree.