Viral Coefficient
Metric measuring how many new users each existing user generates through sharing or referrals, indicating growth potential.
Definition
Viral coefficient calculates the average number of new users that each current user brings to a platform or campaign through organic sharing, tagging, or referrals. A coefficient above 1.0 indicates exponential growth potential.
This metric helps marketers understand content or product virality and optimize sharing mechanisms, referral programs, and social features to amplify organic growth.
Why It Matters
High viral coefficients reduce customer acquisition costs by leveraging existing users to drive growth, making marketing budgets more efficient and enabling rapid scaling.
Understanding viral mechanics helps teams design more shareable content and features, potentially creating self-sustaining growth loops that reduce dependence on paid acquisition.
Examples in Practice
Dropbox achieving a viral coefficient of 0.35 through file sharing that naturally exposed the service to new users' networks.
Instagram's early growth driven by photo sharing to other social platforms, creating exposure among non-users.
Referral programs like Uber's driver and rider incentives creating viral loops where both parties benefit from sharing.