Clear definitions of the metrics, concepts, and signals that impact site speed, search rankings, user behavior, and revenue.
Interaction latency is the time between a click, tap or key press and the screen visibly responding. It's the raw number behind INP.
Learn moreA long task is any piece of browser work that blocks the main thread for more than 50 milliseconds, leaving clicks and taps waiting in line.
Learn moreDNS resolution time is how long the browser takes to turn your domain name into a server address. It's the first delay on every new visit.
Learn moreThe event loop is how the browser decides what to do next on a page. When heavy JavaScript clogs it, clicks and taps have to wait.
Learn moreLearn what First Contentful Paint (FCP) is, why it shapes users' first impression of your website, and how improving it can reduce bounce rates and increase conversions.
Learn morePerformance Optimization is the process of improving your website's speed and responsiveness by reducing loading times and eliminating performance bottlenecks. A faster site creates a better user experience, improves conversions, and helps maximize the value of your traffic.
Learn moreThe Critical Rendering Path is the sequence of steps a browser takes to convert HTML, CSS, and JavaScript into pixels displayed on the screen. Optimizing this process helps pages load faster, improves perceived performance, and creates a smoother user experience.
Learn moreTime to First Byte (TTFB) is a performance metric that shows how quickly your server starts responding after a browser makes a request.
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