PageRank

Google's original algorithm for measuring the importance of web pages based on the quantity and quality of links pointing to them.

PageRank (named after Google co-founder Larry Page) was the foundational innovation behind Google's search algorithm. The core idea: a page is important if important pages link to it. PageRank is calculated recursively — a link from a high-PageRank page passes more value than a link from a low-PageRank page.

Google no longer publicly shares PageRank scores and retired the PageRank Toolbar in 2016. However, PageRank remains a core part of Google's ranking algorithm. Third-party metrics like Ahrefs' Domain Rating (DR), Moz's Domain Authority (DA), and Majestic's Trust Flow approximate PageRank but are not official Google data.

PageRank distributes through links. An internal link from your homepage to a product page passes PageRank internally. A backlink from a high-authority site passes PageRank externally. Pages with higher PageRank are crawled more frequently, indexed more reliably, and tend to rank higher for competitive terms.