Well, Aspose.Cells is a pure .NET library (server side component) that is used to manage Excel spreadsheets at every level. It also supports to render HTML file to Excel file formats (e.g XLS, XLSX, XLSM, CSV, Tab Delimited, ODS etc.). Please note (there are certain limitations): First of all not all the HTML tags are supported. In MS Excel some limited HTML tags are supported (only basic tags are supported in MS Excel too), so Aspose.Cells cannot parse all types of HTML tags as it follows Ms Excel standards and specifications. you may open and render HTML files in MS Excel but the HTML should be MS Excel oriented, this is not completely a common HTML.