Key Performance Indicator
A Key Performance Indicator (KPI) is a quantifiable measure used to evaluate how effectively a company or team is achieving its key business objectives. Good KPIs are specific, measurable, time-bound, and tied to outcomes — not just activity.
A SaaS company's north star KPI might be 'weekly active paying accounts'. Supporting KPIs: trial-to-paid conversion rate, time-to-activate, and expansion MRR.