I have a stacked bar RadHtmlChart that is created programmatically in the code behind. When I create the chart, and set the width to Unit.Pixel(1500), it works fine, as shown in Working.png. However, when I change the value to Unit.Percentage(90), the chart is not rendered properly at all. Any fixes/workarounds for this? Seán For the time being you must set percentage to the chart's wrapper. For example: CSS: <style type="text/css"> html, body, form { padding: 0; margin: 0; height: 100%; overflow: hidden; } .myChart { width: 100% !important; height: 100% !important; } </style> ASPX: <div style="width: 30%; height: 40%; border: 1px solid green;"> <telerik:RadHtmlChart runat="server" ID="RadHtmlChart1" CssClass="myChart" Width="600px" Height="400px"> <PlotArea> <Series> <telerik:ColumnSeries Name="Product 1"> <SeriesItems> <telerik:CategorySeriesItem Y="15000" /> <telerik:CategorySeriesItem Y="23000" /> <telerik:CategorySeriesItem Y="10000" /> </SeriesItems> </telerik:ColumnSeries> </Series> <XAxis> <Items> <telerik:AxisItem LabelText="1" /> <telerik:AxisItem LabelText="2" /> <telerik:AxisItem LabelText="3" /> </Items> </XAxis> </PlotArea> <ChartTitle Text="Product sales for 2011"> </ChartTitle> <Legend> <Appearance Position="Bottom" /> </Legend> </telerik:RadHtmlChart> </div>