# JS API Reference

# Welcome to the Highcharts JS 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.

# lang.accessibility.thousandsSep

Thousands separator to use when formatting numbers for screen readers. Note that many screen readers will not handle space as a thousands separator, and will consider "11 700" as two numbers.

Set to `null` to use the separator defined in lang.thousandsSep.