What are some alternatives?
When comparing dhtmlxSpreadsheet and SpreadsheetConverter.com, you can also consider the following products
ag-Grid - The best HTML5 datagrid in the world
SpreadsheetWEB - SpreadsheetWEB is a no-code platform that helps businesses translate their collective Microsoft Excel expertise into robust web applications with limited or no reliance on IT resources.
EtherCalc - EtherCalc is a web spreadsheet.
Publisheet - Publish your Excel sheets to the web as dynamic web applications with formula support.
Appizy - Convert spreadsheet to web application