Time to First Byte (TTFB) measures how long it takes for a browser to receive the very first byte of data from a server after making a request, reflecting server responsiveness before any actual page content begins to load.
A slow TTFB delays every subsequent step of page loading, directly impacting Core Web Vitals metrics like Largest Contentful Paint, making it one of the most foundational performance metrics to address before optimizing other, later-stage loading factors.
Common causes of slow TTFB include inadequate server resources, lack of caching, inefficient database queries, or server locations physically distant from a site’s primary audience, often addressed through better hosting or a CDN.
TTFB optimization is a foundational element of our Technical SEO service.