Theme-heavy sites
Cut render-blocking CSS impact on complex WordPress themes.
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Feature
Critical CSS
Generate above-the-fold CSS in the cloud and load it from Managed CDN.
Critical CSS extracts the styles needed for above-the-fold rendering so the browser can paint meaningful content sooner. Cache Rocket generates it in the cloud with a real headless browser coverage pass, hosts the result on Managed CDN, and the WordPress plugin injects it where visitors need it.
Highlights
- Real browser CSS coverage—not guesswork
- Served from Managed CDN automatically
- Per-page generation with monthly plan quotas
- Built for WordPress Media workflows
Faster first paint without hand-written CSS
Hand-maintained Critical CSS breaks as themes and page builders change. Cache Rocket regenerates coverage from a live page load, then caps and uploads a compact critical.css for delivery from assets.cacherocket.com.
Critical CSS is available on Pro and Business plans, with monthly page quotas that scale with your tier.
Part of the cloud optimization suite
Combine Critical CSS with image optimization, LQIP, and PageSpeed Insights to measure and improve Core Web Vitals—while cache warmers keep HTML responses hot at the edge.
How it works
- 1
Unlock on Pro+
Confirm Critical CSS is included on your Cache Rocket plan.
- 2
Enable Generate Critical CSS
Turn it on in the WordPress plugin Media settings.
- 3
Generate and inject
Cache Rocket produces critical.css, hosts it on Managed CDN, and the plugin injects it for visitors.
Where it shines
Landing pages
Improve first paint on campaign URLs that must convert quickly.
Core Web Vitals work
Pair with PageSpeed Insights audits to validate improvements.
Frequently asked questions
- Is Unused CSS included?
- Unused CSS appears as a plan entitlement on higher tiers; full productized Unused CSS processing is not the same as Critical CSS generation. Use Critical CSS for above-the-fold delivery today.
- Where is Critical CSS stored?
- Generated files are served from Managed CDN (assets.cacherocket.com) and injected by the WordPress plugin.
- What if I hit my Critical CSS page quota?
- New generation jobs pause until the monthly quota resets or you upgrade.
Related features
All featuresReady to try this in your account?
Create a free Cache Rocket account, verify a hostname, and turn this capability on for your site or API.