2 file types use the .xdl file extension.

What is an XDL file?

Defines the classes and structures of other files created by the Oracle Expert database optimization program; created whenever a database, environment, instance, schema, or workload data is exported by Oracle Expert.

Category: Text Files

XML Schema File

An XDL file may also be an XML schema file that defines the structure, layout, and rules for .XML documents. It specifies which elements and attributes can appear in an XML file, how they are organized, and what types of data they can contain. Developers or system administrators typically create XDL files by using specialized tools like XML editors, schema designers, or applications that generate XML schema definitions automatically.

The XDL format ensures that XML files follow a consistent structure, making it easier for programs to read, write, and validate the data. One of the most common uses of XDL files was in Microsoft InfoPath, a form design and data-gathering tool that was part of the Microsoft Office suite. In that context, XDL files defined the structure of the XML data generated by InfoPath forms, helping other systems process the form data reliably.

Although XML is still used in enterprise environments, formats like JSON have become more popular in web and app development due to their simpler syntax and lighter structure. As a result, XDL files—and tools like InfoPath that depended on them—are less common today. However, in industries such as government, healthcare, or finance, where XML remains a standard, XDL and similar schema files are still used to validate and manage structured data.

You can open XDL files with any text editor, since they are written in XML format. Some options include Microsoft Notepad (Windows), Apple TextEdit (macOS), and Microsoft Visual Studio Code . If the XDL file was created by a specific program, like Microsoft InfoPath, opening it in that program will provide the most context-specific view.

Programs that open XDL files

Updated: April 22, 2025