> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sequenzy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# HTML Blocks

> Insert custom HTML snippets inside the visual email editor

# HTML Blocks

HTML blocks let you drop custom email-safe HTML directly into the block editor without switching the whole email into full-code mode.

Use them when you need a hand-built snippet that is easier to paste as code than recreate with standard blocks.

## What HTML Blocks Are For

* Embedding a custom promo banner or card layout
* Reusing a snippet from another email system
* Adding markup that is too specific for the standard block library
* Mixing custom HTML with regular Sequenzy blocks in the same email

## How To Use Them

1. Open the component panel or type `/html`
2. Insert the **HTML** block
3. Paste your snippet into the inline code editor
4. Review the live preview on the canvas
5. Send a test email before publishing

## What Works Inside The Block

* Inline CSS styles
* Table-based email layouts
* Merge tags like `{{FIRST_NAME}}`, `{{EMAIL}}`, and `{{unsubscribeUrl}}`
* Links that still go through Sequenzy's normal email rendering pipeline

## Best Practices

* Prefer email-safe HTML with inline styles
* Use tables for complex layouts when broad email-client support matters
* Keep the block focused on a snippet, not an entire email document
* Test in real inboxes if you rely on advanced HTML or unusual spacing

## HTML Block vs Full HTML Email

* Use an **HTML block** when you want one custom section inside a larger block-based email
* Use Sequenzy's full HTML import/editor flow when the entire email should be managed as HTML

## Limitations

* HTML blocks are best for snippets, not full standalone HTML documents
* Email clients still have their usual limitations, so browser-only markup may not render as expected
* Scripts are not a valid email pattern and should not be part of your email HTML