Inline, minified critical CSS in seconds β eliminate render-blocking resources, boost Core Web Vitals and rank higher in Google.
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 βfirst screenβ). By inlining this CSS directly in the <head> you remove render-blocking stylesheets, greatly improving Largest Contentful Paint (LCP) and First Contentful Paint (FCP).
Our online generator analyses your HTML, simulates multiple viewports and returns a minified CSS snippet ready to paste into your theme or build pipeline.
Install our free WP plugin or copy the inline CSS into header.php. Add <link rel="preload" as="style"> for the full stylesheet.
Paste the generated snippet in theme.liquid before loading theme.css. Optionally use our API for automated builds.
Run the CLI in your CI pipeline (criticalcss extract ./out --html) and inject the CSS via <style jsx global>.
Built by developers, for developers. Extract critical CSS with precision and speed.
Extract critical CSS in under 50ms. Our optimized engine processes websites faster than any competitor.
Advanced viewport detection ensures 100% accurate above-the-fold CSS extraction for any device.
REST API, webhooks, batch processing, and CLI tools. Integrate seamlessly into your workflow.
Generate critical CSS for mobile, tablet, and desktop viewports simultaneously.
SOC2 compliant with enterprise-grade security. Your data is protected at all times.
Detailed reports showing performance gains, file size reduction, and optimization metrics.
Enter any website URL and extract above-the-fold CSS in seconds
Improve your Core Web Vitals and search rankings with optimized above-the-fold CSS extraction
Critical CSS extraction directly improves your Largest Contentful Paint (LCP) and Cumulative Layout Shift (CLS) scores.
Google uses page speed as a ranking factor. Our critical CSS generator helps you achieve better SEO performance.
Average improvement with critical CSS optimization
Critical CSS is the minimum set of rules needed for above-the-fold content. By inlining it you unblock rendering and speed up perceived load time.
Yes. We offer CMS-specific instructions and a WordPress plugin. For other platforms you can paste the snippet manually or via our API.
Absolutely β see the βDeveloper-First APIβ section above or read the docs at /docs.
Integrate critical CSS extraction into your build process with our powerful REST API
Simple HTTP endpoints for critical CSS extraction
Get notified when extraction is complete
Process multiple URLs simultaneously
Command line interface for automation
Our advanced algorithm analyzes your website and extracts only the CSS needed for above-the-fold content
Our system fetches and analyzes your webpage structure, identifying all CSS resources
We simulate different device viewports to determine what content appears above the fold
Advanced algorithms extract only the CSS rules needed for above-the-fold rendering
The extracted CSS is minified and optimized for maximum performance gains
Simple, Transparent Pricing
Start free, scale as you grow. No hidden fees, no surprise charges.