Female software developer working front of multiple monitors extending functionality for Word, PowerPoint, Excel, and Outlook using Office JavaScript API.

Build powerful applications for Office

Use the Office JavaScript API to extend functionality for Word, Excel, PowerPoint, and Outlook.

Build applications for Excel

Integrate with Outlook

Create add-ins for PowerPoint

Extend Word across multiple platforms

What's new in Office development

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Training and certification

Explore learning paths and become a certified Microsoft 365 developer.

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Bring your solutions to market

Submit your Microsoft 365 App to Microsoft AppSource to make it available to consumers and businesses.

Join the Microsoft 365 Developer Program

Join the Microsoft 365 Developer Program

Get an instant sandbox, tools, and other resources you need to build solutions for the Microsoft 365 platform, including:

  • A free Microsoft 365 E5 developer subscription, preconfigured with sample data, including Teams data
  • Microsoft Graph users, mail, and calendar, Teams, and SharePoint Framework sample data packs
  • Access to a community of Microsoft 365 experts
  • Personalized content recommendations
Join now

Featured tools

Script Lab

Script lab is an Office JavaScript API tool for anyone who wants to learn about writing Office add-ins for Word, Excel, PowerPoint, or Outlook.
Explore Script Lab

Office Scripts

Use Office Scripts in Excel on the web to automate your common tasks. Learn how to create and edit Office Scripts and get started automating today.
Explore Office Scripts

Fluent UI

The official front-end framework for building experiences that fit seamlessly into Microsoft 365.
Explore Fluent UI

Developer Tools

Use our developer tools to build solutions for consumer and professional markets.
Explore developer tools

Office developer community


Ask questions on Microsoft Q&A.

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Feature requests

Request a feature on Microsoft Tech Community.

Request a feature

Office assisted support

Premier/Unified Support customers get enterprise-level support for Office development.

Open a support request

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