How to Format XML in Python

Format XML with xml.dom.minidom (built-in)

Python's standard library includes xml.dom.minidom — no installation needed. The toprettyxml() method formats parsed XML with indentation.

import xml.dom.minidom

xml_string = '<root><name>Alice</name><age>30</age></root>'

dom = xml.dom.minidom.parseString(xml_string)
formatted = dom.toprettyxml(indent='  ')
print(formatted)

Remove the Extra XML Declaration Line

toprettyxml() adds <?xml version="1.0" ?> at the top. To strip it:

import xml.dom.minidom

dom = xml.dom.minidom.parseString(xml_string)
lines = dom.toprettyxml(indent='  ').split('\n')
# Skip the first line (XML declaration)
formatted = '\n'.join(lines[1:])
print(formatted)

Format an XML File

import xml.dom.minidom

# Read and reformat an XML file
with open('data.xml', 'r') as f:
    xml_string = f.read()

dom = xml.dom.minidom.parseString(xml_string)
formatted = dom.toprettyxml(indent='  ')

with open('data_formatted.xml', 'w') as f:
    f.write(formatted)

Format XML with lxml (third-party)

lxml is faster and more feature-rich than minidom. Install with pip install lxml.

from lxml import etree

xml_string = b'<root><name>Alice</name><age>30</age></root>'

root = etree.fromstring(xml_string)
etree.indent(root, space='  ')
formatted = etree.tostring(root, pretty_print=True).decode()
print(formatted)

Format XML from Command Line (Python one-liner)

# Format XML file via command line
python3 -c "
import xml.dom.minidom, sys
print(xml.dom.minidom.parse(sys.argv[1]).toprettyxml(indent='  '))
" data.xml

Need to format XML without writing code?

Paste any XML into the free online formatter — instant results, no Python environment needed.

Frequently Asked Questions