> 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/reference-lines-and-reference-range/introduction.md).

# Introduction

The xViz Gantt Chart provides you with the option to display **Reference Lines** (based on dates) and **Reference Ranges** on the chart thereby giving an indication of where you are in the project and to assess the level of completeness.

**Reference Line** - A date line spanning across all the tasks. Configuration of one date will add the reference line on the Chart.

<img src="/files/pkEHGF9vTEhU2hQayYOo" alt="Image 1: Reference Line in the xViz Gantt Chart" width="563">

**Reference Band** - Range of continuous dates highlighted in the tasks. Configuring two dates ranges will be highlighted as a band in the chart.

<img src="/files/EoktRuKF2xmf1snlCd7j" alt="Image 2: Reference Band in the xViz Gantt Chart" width="563">

{% hint style="success" %}
We can display the Reference line and Reference Range with Static Approach using the Reference tab which is located in Advance Editor - [Static Approach](/project-management/reference-lines-and-reference-range/static-approach.md)
{% endhint %}