Metrics are the quantifiable data points used to measure the performance of content, campaigns, or channels on a platform. On YouTube, core metrics include views, watch time, watch hours, engagement rate, click-through rate (CTR), retention rate, impressions, subscribers, and conversion rate. Together, these metrics form the foundation of data analytics and insights — enabling creators and brands to assess what is working, identify growth opportunities, and optimize their marketing strategy. Metrics are also the basis for defining key performance indicators (KPIs) and conducting benchmarking against industry standards.