Highcharts.chart('container', {

    title: {
        text: 'Highcharts sourceWidth and sourceHeight demo'
    },

    subtitle: {
        text: 'The on-screen chart is 600x400.<br/>The exported chart is 800x400<br/>(sourceWidth and sourceHeight multiplied by scale)',
        floating: true,
        align: 'left',
        x: 60,
        y: 50
    },

    xAxis: {
        categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
    },

    series: [{
        data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4]
    }],

    exporting: {
        sourceWidth: 400,
        sourceHeight: 200,
        // scale: 2 (default)
        chartOptions: {
            subtitle: null
        }
    }

});