Skip to main content
Skip to main content
Microsoft 365

Open XML SDK goes open source

Brian Jones is the principal GPM of the Office Development Platform.

Today is an exciting day for Office developers—we’re open sourcing the Open XML SDK on GitHub! We’re eager to work with the community on continual improvements to the SDK’s functionality and scalability, and to explore new platforms and technologies to support developer platforms such as Mono, an open source implementation of .NET Framework. It’s been over seven years since we released the initial preview of the Open XML SDK, and over that time it’s been one of the key tools developers have used for building solutions that consume, create, and modify Office documents.

I encourage you to head over to GitHub and take a look at the project. We’d love your participation! We posted it under the .NET Foundation. In addition to the SDK itself, we opened all of the Open XML conceptual documentation in MSDN for public review/contributions. A living copy of the docs is now in GitHub for you to edit and review. Pull requests welcome!

The Open XML SDK is a key piece of our overall developer platform. The trends around mobile apps connected to the cloud have expanded the role that Office documents can play in solutions. Many of our Fortune 100 customers have built solutions leveraging the SDK, especially in the banking and health care sectors. We average over 10,000 downloads a month, and the SDK is also widely distributed in other software packages, such as accounting tools.

Here’s a chart that shows a breakdown of the types of solutions people are using the SDK for:
Open XML SDK Use
People are using the OpenXML SDK to create many types of solutions.

When we released version 2.0 of the SDK (in 2008), we saw a huge pick-up in the types of solutions you could build. Version 1.0 helped you navigate the OPC package, but it didn’t help with XML manipulation. With version 2.0 and above, we provide a set of strongly typed objects for each element. In our first blog post on this, Zeyad gave a great overview of the model, and also provided this “hello world” example:


In another post, we provided a great drilldown into the architecture of the SDK and a ton of great examples.

As you’ve probably noticed lately, we’re making a big push to open a lot of our developer technologies to the community. We have a few really cool projects already in GitHub, like the Office 365 SDK for Android Preview, as well as the Open XML package editor. We’ve shifted the Office extensibility model to use open standards like HTML and JavaScript, and we’re exposing Office 365 data (documents, mail, and calendars) through RESTful APIs leveraging oAuth. You’ll see us continue to do more of this, and we’d love to hear any feedback you might have on our UserVoice.

If you’re already an Open XML developer, this is definitely an exciting day. If you haven’t built solutions yet on Open XML, I strongly encourage you to go take a look and try out some of the examples. You’ll be surprised by what you can build.

—Brian Jones

You may also like these articles

Image for: Small business professional working on designs using devices running PowerPoint and Microsoft Teams.
• 4 min read

Power your digital transformation with insights from Microsoft Productivity Score

Editor’s Note: The Mechanics video embedded in this blog post has been updated to reflect some of the product changes announced on December 1, 2020. For some time now, business leaders have made digital transformation a priority. But when the pandemic hit this spring, adopting and embracing digital technology went from being a matter of…

Image for: A man is using his Lenovo laptop like a tablet while sitting in a comfortable chair in a Modern office setting
• 6 min read

Microsoft Productivity Score and personalized experiences—here’s what’s new to Microsoft 365 in October

As I reflect on an action-packed few weeks, I’m struck by how much work has evolved in these past months. And I know our customers feel it too. After quickly moving to remote and hybrid work models this spring, organizations are now seeking sustainable ways to help people collaborate, be productive, and prioritize their wellbeing…

Image for: Microsoft employees working remotely.
• 5 min read

Working remotely during challenging times

A Shanghai-based Microsoft employee shares lessons of working remotely during the COVID-19 outbreak.