---
type: "Article"
title: "Render Cost & Main Thread Blocking Time"
description: "Google's render_cost metric drives crawl frequency — serving prerendered HTML cuts CPU load up to 87% per page."
resource: "https://prerender.info/blog/render-cost-main-thread-blocking-time"
tags: [Technical Architecture, render cost SEO, main thread blocking, Googlebot CPU, render_cost metric, prerendering performance]
timestamp: 2026-04-29T00:00:00Z
---

# Render Cost & Main Thread Blocking Time

Google's render_cost metric drives crawl frequency — serving prerendered HTML cuts CPU load up to 87% per page.

## Source

Generated from prerender.info editorial content (single source of truth). The canonical, always-current version is the `resource` URL above. Claims reflect prerender.info / ostr.io editorial guidance and are not confirmed from third-party public documentation unless explicitly linked.