Microsoft opens up Excel to custom data types with images, arrays, and more

Microsoft Excel used to only allow two types of data: text and numbers. After overhauling Excel with its own live custom data types last year, Microsoft is opening up Excel to give developers the freedom to create their own custom data types that can contain images, arrays, and more.

A new JavaScript API will be available to preview inside Excel later this month, which will let developers create these custom data types for inputs and outputs and enable custom functions. Excel developers will be able to create their own add-ins or update existing ones to use the JavaScript API.

This will open Excel up to far more custom data types, including content cards, images, matrices, arrays, and formatted number values. Excel has long had support for macros and add-ins, but Microsoft’s new APIs should make this a lot more efficient and easier for developers to implement.

“These more flexible structures give you the ability to organize complex data as objects and expose this data to users in more natural ways,” explains Wangui McKelvey, general manager of Microsoft 365. “You can share the power of data types across your entire organization and create add-ins or solutions which can connect data types to your own service or data.”

A preview of the new JavaScript API in Excel will be available later this month, but it’s not clear exactly when this will be rolled out to all Microsoft 365 users.