# Hidden Class

An engine optimization that internally groups objects with the same property layout.

## What is **Hidden Class** in JavaScript?

**Hidden Class** — An engine optimization that internally groups objects with the same property layout.

Level: Master · [More JavaScript terms at this level](https://www.ask-codey.com/glossary/subjects/javascript/master)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/hidden-class