ClosedXML

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.

Install the library through .NET CLI

C:\source> dotnet add package ClosedXML

ClosedXML allows you to create Excel files without the Excel application. The typical example is creating Excel reports on a web server.

using var workbook = new XLWorkbook();
var worksheet = workbook.AddWorksheet("Sample Sheet");
worksheet.Cell("A1").Value = "Hello World!";
worksheet.Cell("A2").FormulaA1 = "MID(A1, 7, 5)";
workbook.SaveAs("HelloWorld.xlsx");