# xml-validate > XMLStarlet toolkit: Validate XML documents. > More information: . - Validate XML document for well-formedness only (default): `xml validate --well-formed {{path/to/input1.xml|URI}} {{input2.xml ...}}` - Validate XML document against Document Type Definition (DTD): `xml validate --dtd {{path/to/schema.dtd}} {{path/to/input1.xml|URI}} {{input2.xml ...}}` - Validate XML document against XML Schema Definition (XSD): `xml validate --xsd {{path/to/schema.xsd}} {{path/to/input1.xml|URI}} {{input2.xml ...}}` - Validate XML document against a Relax NG schema (RNG): `xml validate --relaxng {{path/to/schema.rng}} {{path/to/input1.xml|URI}} {{input2.xml ...}}` - Display help for `validate` subcommand: `xml validate --help`