ClosedXML is a .NET library for reading, manipulating and writing Excel 2007+ (.xlsx, .xlsm) files. It aims to provide an intuitive and user-friendly interface to dealing with the underlying OpenXML API.
Source: ClosedXML
License: MIT / Open source project
Doc: https://closedxml.readthedocs.io/en/latest/index.html
Wiki: https://github.com/closedxml/closedxml/wiki
ClosedXML is a wrapper of the offical .NET Open XML SDK:
https://github.com/dotnet/Open-XML-SDK