# HTML validation

Checking markup against HTML's conformance rules to find mistakes.

## What is **HTML validation**?

Checking markup against HTML's conformance rules to find mistakes.

Level: Novice · [More HTML terms at this level](https://www.ask-codey.com/glossary/subjects/html/novice)

Updated: October 16, 2026

Source: https://www.ask-codey.com/glossary/html-validation