How to Make an XML File: A Simple Step-by-Step Guide

An XML file stores information in a structured, readable format that software can parse. You can make one with a basic text editor; you do not need a special XML program to get started. Before writing, find out whether the system that will read the file requires particular element names, attributes, or a schema. XML syntax is flexible, but the receiving application may expect a specific structure.

What You’ll Need

A plain-text editor, such as Notepad, TextEdit in plain-text mode, or a code editor. Avoid rich-text formatting, which can add hidden characters.
A filename ending in .xml, such as contact.xml.
If the file must meet a particular format, its instructions, sample file, or schema. A schema is a set of rules describing allowed elements and values.

Step-by-Step

Check the expected format. If an app, website, device, or organization requested the XML, look for a template or documentation first. Confirm the required element names, order, capitalization, and whether the file needs a schema reference. XML itself does not define what a tag such as <name> means; the software using the file does.
Open a plain-text editor. Create a new file in a text editor or code editor. If using a word processor, switch to plain-text mode or choose a plain-text document format. Do not start with a formatted document and simply change its extension: that does not turn it into XML.
Add the XML declaration. At the top, you can add <?xml version="1.0" encoding="UTF-8"?>. This identifies the XML version and character encoding. The declaration is commonly used, though some simple XML documents can omit it. If you include it, put it first, before comments or other content.
Create one root element. Every XML document must have exactly one top-level element that contains the rest of the document. For example, start with <contacts> and finish with </contacts>. Choose a descriptive name, and check whether the target system requires a specific one.
Add child elements for the information. Put related information inside the root element, using matching opening and closing tags. This example represents one contact:
<?xml version="1.0" encoding="UTF-8"?> <contacts> <contact> <name>Jordan Lee</name> <email>jordan@example.com</email> </contact> </contacts>
Indenting nested lines makes the structure easier to read, but indentation is usually for readability rather than meaning.
Close and nest tags correctly. Each opening tag needs a matching closing tag, with the same spelling and capitalization. Close inner elements before outer ones. For example, <contact><name>Jordan</name></contact> is properly nested; crossing the closing tags is not. XML is case-sensitive, so <Name> and <name> are different names.
Escape special characters in text. Use & for an ampersand, < for a less-than sign, and > for a greater-than sign when they appear as text. For example, write Research & Development to display “Research & Development.” Quotation marks inside attribute values must also be handled appropriately, usually by choosing the other quote style or using an entity.
Save with the XML extension. Choose Save As, enter a name such as contacts.xml, and select plain text if the editor asks for a format. On Windows, check that the editor has not added .txt, producing contacts.xml.txt. On macOS or other systems, make sure the editor has not saved a rich-text file such as .rtf.
Validate the file. Reopen it in the editor and check the contents and actual filename. Then use an XML validator, an XML-aware editor, or the application that will import it. A basic parser can detect malformed syntax; a schema validator can also check whether the file follows the required vocabulary and structure.

Common Mistakes

Using mismatched tags: <item> must end with </item>, not </items>. A tiny spelling or capitalization difference can prevent parsing.
Forgetting the root: Two separate top-level elements are not a well-formed XML document. Place them both inside one root element.
Saving in the wrong format: A file named data.xml can still contain rich text or be saved as data.xml.txt. Confirm its format and full extension.
Putting special characters directly in text: An unescaped ampersand can be interpreted as the start of an entity. Escape it as &.
Assuming well-formed means correct: A file can follow XML syntax but still fail an importing program because its tags, required fields, or values do not match that program’s specification.

Tips

Start with a small example and add data gradually. Validate after changes to make errors easier to locate.
Use consistent indentation and descriptive element names. Keep the same naming style throughout the document.
Use attributes for short details that describe an element and child elements for content that needs its own structure. The format expected by the receiving system takes priority over personal preference.
Keep a copy of the original file before making major edits, especially if another system relies on it.
For repeated records, place each record inside the same parent element so the structure is consistent.

Troubleshooting

If a validator reports an error, read its line and column number, then inspect that spot and the line immediately before it. The actual mistake may be an unclosed tag earlier in the file, since a parser can only report where the structure became impossible to read.

If the file will not open or import, confirm that it is plain text and that the extension is truly .xml. Check for an unexpected byte-order mark or encoding mismatch if the receiving software reports a character problem; saving as UTF-8 is a common fix, but follow the application’s requirements. If the XML parses but the import still fails, compare its exact tag names, required fields, and value rules with the target system’s template or schema. A syntax validator cannot confirm that your data has the meaning the application expects.

Frequently Asked Questions

Do I need special software to make an XML file?

No. Any plain-text editor can create one. An XML-aware editor is helpful because it can highlight tags and point out some syntax errors, but it is not required.

Can I create an XML file in Notepad?

Yes. Type the XML as plain text, then use Save As and give the file an .xml extension. Check that Windows has not added .txt to the filename.

What is the difference between XML and HTML?

Both use tags, but HTML has standard elements for displaying web pages, while XML lets a document use names suited to its data and application. XML does not automatically define how its content should look on screen.

Does every XML file need a declaration?

No. The declaration is common and can identify the XML version and encoding, but it is not required in every document. If you use one, place it at the beginning.

How can I tell whether my XML is valid?

Use an XML parser or validator to check that it is well-formed. If it must follow a particular schema, validate against that schema too; a well-formed file may still not meet an application’s requirements.

Can I open an XML file in a browser?

Many browsers display XML as a text tree, but they may not show it as a formatted webpage. Use a text or XML editor to make changes, and check the result in the software that needs the file.

Further reading: W3C. Details can change, so check the official page for anything that matters to you. Spotted a mistake? Tell us. How we write an answer.