> For the complete documentation index, see [llms.txt](https://docs.xviz.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.xviz.com/project-management/timeline-configurations/header-levels.md).

# Header Levels

### Header Levels

Timeline has three Header levels:

<img src="/files/bUoHpaCoLjhDy680VuBt" alt="Image 1: Timeline level Settings" width="257">

* Top Level
* Middle Level
* Low Level

Toggle on/off to enable the zoom levels.

{% hint style="warning" %}
We do not provide an option for adjusting the low-level header height because it is automatically calculated within the visual as follows:

Low Level Header Height = Chart Options Header Height - Top Level Header Height - Mid Level Height
{% endhint %}