EPPlus

EPPlus was founded as an open source project by swedish programmer Jan Källman in 2009. At the time the Office Open XML standard for representing spreadsheets was relatively new and there wasn´t much available in the .NET space. After a few years he was joined by his brother Mats Alm. The project provided an opportunity for the two brothers, both programmers since they were fighting over a Commodore 64 in the eighties, to build something together.

Thanks to its feature richness, performance and quality EPPlus soon became popular among .NET developers all over the world. As of 2021 it is by far the most downloaded spreadsheet library on Nuget with over 30 million downloads since the start.

EPPlus Software AB

Jan Källman and Mats Alm founded EPPlus Software AB in 2019 to be able to work full time with EPPlus. With families and full time jobs, it had become increasingly challenging for them to maintain and develop a project of this size on their spare time. During 2019 the download rate increased massively - the project has been asked to provide input on proposed changes to the Office Open XML standard and in 2019 Microsoft used EPPlus to demonstrate their new Blazor web assembly framework at various developer conferences. Thousands of companies and organizations depend on EPPlus for managing their spreadsheet data every day.