Viral Coefficient (K-factor)
The average number of new users each existing user invites, indicating organic growth potential.
The viral coefficient (K-factor) measures the average number of new users each existing user invites who actually convert. K-factor = (invites sent per user) × (conversion rate of invites). K > 1 indicates true viral growth (users compound on themselves); K < 1 indicates supplemental growth (viral lifts CAC but doesn't sustain). Most B2B products have K-factors of 0.1-0.5 — meaningful but not standalone. Empire325 instruments viral metrics into product analytics for SaaS clients with referral or invitation flows.
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Performance Analytics
Marketing measurement, MMM, and incrementality testing to prove ROAS at the channel and creative level.
Explore Performance Analytics →Related terms
Marketing Attribution
The practice of assigning credit for a conversion to specific marketing touchpoints across the customer journey.
Customer Acquisition Cost (CAC)
Total marketing and sales investment divided by new customers acquired in a period.
Customer Lifetime Value (LTV)
Total revenue (or gross profit) a single customer generates over the entire relationship.
Conversion Rate Optimization (CRO)
The systematic discipline of increasing the percentage of visitors who complete a desired action.