Today, we are pleased to announce the general availability of the Microsoft Excel REST API for Office 365—now developers can use Excel to power custom apps. Excel is an indispensable productivity tool; users across all industries and roles embrace it. It is used for everything from simple task tracking and data management, to complex calculations and professional reporting. With our new interface, Excel for Office 365 can extend the value of your data, calculations, reporting and dashboards.

The Excel REST API release is a continuation of our journey to make Office an open platform for developers. The Office developer framework uses modern web development standards, so developers can build smarter apps that operate as part of Office on mobile, web and desktop platforms. The new Excel interface is exposed through the Microsoft Graph to access to intelligence and insights from the Microsoft cloud.

Here are a few scenarios how developers can use the new Excel REST API:

Excel as a calculation service

Users love the ease with which they can perform deep and complex calculations within Excel. Developers can now access Excel’s powerful calculation engine with instant results. For example, a mortgage calculator can take advantage of the PMT function from Excel—using a simple API call including principal, rate and number of payments. Excel does all the heavy lifting and returns the monthly payment instantly. With more than 300 Excel worksheet functions available, you have full access to the breadth of formula supported by Excel today. Complex business models don’t need to be rebuilt repeatedly; developers can leverage Excel to perform those calculations instantly and retrieve the results with simple API calls.

Excel as a reporting service

Excel is a reporting hero, from simple data tables to professional dashboards. Today, we are giving developers full access to all of Excel’s reporting features—making Excel an online reporting service within Office 365. Imagine any of the reporting scenarios users rely on today pulled into a custom app to create professional charts or analyze large sets of data intelligently, seamlessly blending Excel into those customized experiences.

Excel as a data service

Excel is also a great tool to store and track data. If your information is stored in a workbook, that data is available to any app integrating with Office 365, making its contents available to read from custom solutions and enabling them to use Excel as the data storage.

We look forward to working with developers and partners to discover and build new places and scenarios where Excel will continue to enable people to be more productive. Companies are already taking advantage of our new Excel REST API, including:

Zapier lets users easily automate tedious tasks. Zapier recently announced a new Excel integration, powered by Excel REST API, with near-infinite use cases, like simplifying a data collection process. Users can now build zaps where data is automatically added into Excel from other services, like emails and surveys, making Excel the data repository for all your connected services.

Sage is working on integrating Sage 50 accounting software with Office 365, leveraging Excel via the new Excel REST API to access and combine business data in Sage 50 with the productivity benefits of Office. With powerful interactive Microsoft Excel reporting and business performance dashboards, Sage has simplified how to interact with the data and enabled small and medium businesses to make sense of data quickly—and make faster, better decisions.

Want to build custom apps using Excel?

Excellent! Visit dev.office.com/excel/rest, where you’ll find documentation and code samples to help you get started. It only takes a few lines of code to set up a basic integration with our Excel to-do list. Once you jump in, tell us what you think. Give us your feedback on the API and documentation through GitHub and Stack Overflow, or make new feature suggestions on UserVoice.

—The Office Extensibility team