ClosedXML/ClosedXML

a .NET library that can read/write Office formats without Microsoft Office installed. No COM+, no interop.

Open XML SDK by Microsoft

Excel Workbook Manager

Go language library for reading and writing Microsoft Excel™ (XLAM / XLSM / XLSX / XLTM / XLTX) spreadsheets

Lightweight, fast and native cross-platform processing tool for importing and exporting spreadsheet documents.

Lightweight and fast library written in C# for reading Microsoft Excel files

Main engine of the IronCalc ecosystem

xlwings is a Python library that makes it easy to call Python from Excel and vice versa. It works with Excel on Windows, macOS, and Excel on the web.

A pure PHP library for reading and writing spreadsheet files