The Excel Services REST and SOAP APIs introduced in SharePoint 2010 are SharePoint only, but with the Excel Services JavaScript API you can work with embedded workbooks on a host web page — from ...

At its Ignite conference, Microsoft today announced an update to Excel that brings a new JavaScript API to the venerable spreadsheet app. With this new API, developers will be able to create ...

This is shown in the image below where we see Microsoft Excel Web Content, which is the hidden browser with CoinHive loaded, utilizing 206% of the computer's 4 cores. CPU Utilization ...

At the Build 2018 developer conference that's taking place these days in Seattle, USA, Microsoft announced support for custom JavaScript functions in Excel.