Highcharts Shared tooltip on the overlapped points

author(s): Malinga Perera

by Malinga

HTML

<script src="http://code.highcharts.com/highcharts.js"></script>
<div id="container" style="height: 400px"></div>

JavaScript

$(function () {
    var series1 = [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4];

    var series2 = [24.9, 50.5, 106.4, 90.2, 80.0, 150.0, 160.6, 170.5, 160.4, 180.1, 95.6, 54.4];

    $('#container').highcharts({
        xAxis: {
            categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
        },
        tooltip: {
            formatter: function () {
                var s1 = this.series.chart.series[0].processedYData[this.point.index];
                var s2 = this.series.chart.series[1].processedYData[this.point.index];
                if (s1 == s2) {
                    return '<b>' + this.series.chart.series[0].name + ' :' + s1 + '</b><br/><b>' + this.series.chart.series[1].name + ' :' + s2 + '</b><br/>in month : ' + this.x;
                }
                return '<b>' + this.series.name + ' :' + this.y + '</b><br/>in month : ' + this.x;
            }
        },
        series: [{
            data: series1
        }, {
            data: series2
        }]
    });
});