A validator is a computer program used to check the validity or syntactical
correctness of a fragment of code or document. The term is commonly used in the
This validator checks the markup validity of Web documents in HTML, XHTML,
SMIL, MathML, etc. If you wish to validate specific content such as RSS/Atom ...
The W3C validators are hosted on server technology donated by HP, and
supported by community donations. Donate and help us build better tools for a
A validator is a callable that takes a value and raises a ValidationError if it doesn't
meet some criteria. Validators can be useful for re-using validation logic ...
Unlike HTML validators
, accessibility validators
require that you do a bit more manual work to make sure that your sites are accessible. This document will help you understand how to use an accessibility validator
so that your site actually is accessible. More »
FormValidation comes with various built-in validators listed in ...
An implementation of the HTML5 parsing algorithm in Java in the form of an
online tool. Several presets and options.
An online RELAX NG validation service. Supports multiple schemas at a time.
A library of string validators and sanitizers. ... Install the library with npm install
Manually Creating Validators; Form Request Validation. Working With Error
Messages. Custom Error Messages. Available Validation Rules; Conditionally ...