Calibre has launched Real User Monitoring (RUM) on all plans, including the free trial. Unlike competitors' sprawling APM products, Calibre RUM is designed to be focused, privacy-first, and lightweight. It captures Core Web Vitals and UX signals from anonymized browser sessions, ranks pages by traffic and impact, provides element-level attribution (identifying specific DOM elements causing poor LCP, INP, or CLS), and segments audience data by country, device, browser, and OS. RUM complements Calibre's existing synthetic and CrUX monitoring, giving teams three data sources for web performance. Setup requires a single script tag, with predictable session-based pricing starting at 5,000 sessions per month.
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Why RUM? Why now? #Fast websites don’t just happen by themselves #What you get with Calibre RUM #Our approach #Get started #Sort: