# Welcome to the Highcharts Gantt JS (gantt) Options Reference

These pages outline the chart configuration options, and the methods and properties of Highcharts objects.

Feel free to search this API through the search bar or the navigation tree in the sidebar.

# tooltip.format

A format string for the whole shared tooltip. When format strings are a requirement, it is usually more convenient to use `headerFormat`, `pointFormat` and `footerFormat`, but the `format` option allows combining them into one setting.

The context of the format string is the same as that of the `tooltip.formatter` callback.