google.charts.load('current', {'packages':['corechart']});
google.charts.setOnLoadCallback(drawChart);
function drawChart() {
var dataTable = new google.visualization.DataTable();
dataTable.addColumn('string', 'Country');
// Use custom HTML content for the domain tooltip.
dataTable.addColumn('number', 'Gold');
dataTable.addColumn({'type': 'string', 'role': 'tooltip', 'p': {'html': true}});
dataTable.addColumn('number', 'Silver');
dataTable.addColumn({'type': 'string', 'role': 'tooltip', 'p': {'html': true}});
dataTable.addColumn('number', 'Bronze');
dataTable.addColumn({'type': 'string', 'role': 'tooltip', 'p': {'html': true}});
dataTable.addRows([
['USA',46, createCustomHTMLContent(1), 29, createCustomHTMLContent(2), 29, createCustomHTMLContent(3)],
['China', 38, createCustomHTMLContent(4), 27, createCustomHTMLContent(5), 23, createCustomHTMLContent(6)],
['UK', 29, createCustomHTMLContent(7), 17, createCustomHTMLContent(8), 19, createCustomHTMLContent(9)]
]);
var options = {
title: 'London Olympics Medals',
colors: ['#FFD700', '#C0C0C0', '#8C7853'],
// This line makes the entire category's tooltip active.
// Use an HTML tooltip.
tooltip: { isHtml: true }
};
// Create and draw the visualization.
new google.visualization.ColumnChart(document.getElementById('charts')).draw(dataTable, options);
}
function createCustomHTMLContent(a) {
return '<div>' + a + '</div>';
}
<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
<div id="charts"></div>