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CSS Validator

Verify your CSS syntax, balance curly brace blocks, and locate missing property semicolons.

Interactive Online Utility

CSS Validator runs 100% locally in your browser sandbox with zero network roundtrips. Load or paste your code directly into the workspace above to format, parse, validate, or generate your output instantly. 

.card {
  background-color: #fff;
  border-radius: 8px
  padding: 16px;
}
PRO TIP Local Client-Side Processing

Otuls runs 100% locally in your browser. Your data is processed in-memory and never transmitted over external network connections.

Technical Guide & Overview

CSS Validator is a dedicated developer utility designed to streamline common workflow tasks with zero installation, instant execution, and complete data privacy.

How It Works Under the Hood

The tool leverages modern browser standards (HTML5, WebAssembly, WebGL, and modern ECMAScript) to execute complex computations directly on your local device CPU and GPU without offloading processing to third-party cloud servers.

Authoritative Specifications & Primary Standards

Official specifications, RFCs, and authoritative open-source repositories for CSS Validator:

W3C Standard

Official W3C service verifying CSS style sheets against formal recommendations.

GitHub Repository

Leading open-source linter enforcing CSS standards and catching syntax errors.

Zero-Knowledge Client-Side Sandboxing

Privacy First: This tool operates completely inside your browser with zero remote logging or tracking.

Frequently Asked Questions

Q: Can it catch missing semicolons?

Yes! It checks CSS properties in your selectors block and warns you if standard declarations do not terminate with a semicolon.