🚀 Getting Started with criticalcssgenerator.com

Welcome to criticalcssgenerator.com — the fastest, most precise critical CSS generator trusted by over 100 developers. Instantly extract above-the-fold CSS, eliminate render-blocking styles, and improve your Core Web Vitals with ease.

Critical CSS Generator: Inline, minified critical CSS in seconds – eliminate render-blocking resources, boost Core Web Vitals, and rank higher on Google.

✨ Features

  • Lightning Fast: Extract critical CSS in under 50ms.
  • Pixel Perfect Extraction: Accurate above-the-fold CSS for any device.
  • Developer Tools: REST API, CLI, webhooks, batch processing.
  • Multi-Device Support: Generate for mobile, tablet, desktop, simultaneously.
  • Enterprise Security: SOC2 compliant, your data is always protected.
  • Performance Analytics: Detailed performance and optimization metrics.

🛠️ How It Works

Our advanced engine analyzes your site in four simple steps:

  1. 🔍 URL Analysis: Fetches and maps your site’s HTML and CSS.
  2. 📱 Viewport Simulation: Simulates real devices and multiple screen sizes.
  3. ⚡ CSS Extraction: Identifies only the CSS needed for above-the-fold content.
  4. 🎯 Optimization: Minifies and prepares the critical CSS snippet, ready to paste into your project.

Supported Platforms

  • WordPress/WooCommerce: Use our free plugin or add CSS to header.php.
  • Shopify/Liquid: Paste CSS in theme.liquid above your main stylesheet.
  • React/Next.js: Inject via <style jsx global>, or automate with our CLI.
  • Any CMS: We auto-detect and optimize for popular platforms.

💰 Pricing

CriticalCSS.dev is free to start. No credit card required.

Plan Price Extractions API Access Support
Free $0/mo 5/hr ✗ Community Support
Pro $29/mo 1,000/mo ✓ Priority Support
Enterprise Custom Unlimited ✓ + SLA Dedicated/SLA

Start Free • Upgrade to Pro • Contact Sales

🧑‍💻 REST API & CLI

Integrate critical CSS extraction into your build process with our API and CLI.

🔌 API Example

http
POST /api/v1/extract
Content-Type: application/json

{
  "url": "https://example.com",
  "viewport": "1920x1080" 
}

CLI Tool

npm install -g @criticalcss/cli
criticalcss extract https://example.com

Dashboard

Manage your usage, run extractions, and view analytics from your Dashboard.

Logout

Logout safely at any time.

What is Critical CSS?

Critical CSS (also called above-the-fold CSS or critical path CSS) is the minimal set of styles required to render the portion of a webpage visible without scrolling ("the first screen").

Inlining this CSS in the <head> eliminates render-blocking stylesheets and significantly improves:

  • Largest Contentful Paint (LCP)
  • First Contentful Paint (FCP)
  • Google PageSpeed scores
  • SEO and mobile experience

Our generator crawls your HTML, simulates real devices, and returns a minified CSS snippet ready to use.

SEO Optimization

Critical CSS optimization directly improves your Core Web Vitals and search results:

  • 🚀 Reduce LCP by up to 40%
  • ✓ Eliminate render-blocking CSS
  • ✓ Improve First Contentful Paint (FCP)
  • 📈 Higher search rankings
  • ✓ Faster page load times and better mobile experience

95+ average PageSpeed score after optimization

Frequently Asked Questions

What is Critical CSS and why is it important?
Critical CSS is the minimal CSS needed to render the above-the-fold content of your page without delay.

Does this tool support WordPress, Magento, Shopify?
Yes, our tool works with all major platforms and frameworks.

Is there an API or CLI for automation?
Yes, use our REST API or CLI to automate extraction in your workflow.

Example: Generate Critical CSS

It's easy to generate critical CSS for any website:

  1. Enter your website URL into the CriticalCSS.dev generator.
  2. Choose your method (PurgeCSS, UnCSS, DropCSS, Critical, etc.).
  3. Click "Extract Critical CSS".
  4. Copy the generated CSS snippet.
  5. Paste it inside the <head> tag of your website, above your main stylesheet link.

Sample Workflow

  1. Go to: https://criticalcssgenerator.com/
  2. Enter your domain, e.g. https://example.com
  3. Click Extract
  4. Copy the suggested critical CSS:
/* Example output */
.header, .hero { ... }
@media (max-width:600px){ ... }
/* Minified, above-the-fold styles */
  1. Add it to your site's <head> section before loading your main CSS file.

Platform-specific Tips

WordPress / WooCommerce

  • Paste the snippet in your header.php file, before loading style.css.
  • Optionally, use the WordPress plugin for automation.

Shopify / Liquid

  • Add the CSS snippet just before including your main theme.css in theme.liquid.

React / Next.js

  • Use the CLI in your build pipeline:

    criticalcss extract ./out --html
  • Inject the resulting CSS via