The viral coefficient (K) measures how many new users each existing user brings in. Formula: K = (Invites sent per user) × (Conversion rate of invites). If K > 1, your product grows exponentially without any paid acquisition. If K is 0.3, each user brings in 0.3 additional users — still helpful but not viral. Most B2B products have K < 0.5; K > 1 is the exceptional case (Slack early days, Zoom during COVID).
For example, if on average each user invites 3 people and 30% of those accept, your K = 0.9 — close to viral but not quite there; improve the invite flow or incentivize invitations to push it past 1.
We audit viral loops for PLG clients — identifying where referral mechanics are breaking down and optimizing them to maximize organic growth.
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We implement Viral Coefficient strategies for B2B tech startups every day. Book a free 30-minute call to get a concrete plan for your situation.
Book a free strategy call →Go-to-Market Strategy (GTM)
GTM is the complete plan for how you bring a product to market: who you're selling to (ICP), what problem you solve (positioning), how you reach them (channels), what you charge (pricing), and how sales and marketing work together.
Product-Market Fit (PMF)
Product-market fit is when your product satisfies a real market need strongly enough that customers come back, expand, and refer others without heavy marketing.
Positioning
Positioning is how you define your product in relation to alternatives in the mind of your target customer.
Messaging
Messaging is how your positioning translates into specific words: headlines, taglines, elevator pitches, email copy, and ad creative.
Brand Awareness
Brand awareness is the degree to which your target market recognizes and recalls your brand.
Buyer Persona
A buyer persona is a semi-fictional profile of your ideal buyer — their job title, responsibilities, goals, pain points, objections, and how they prefer to buy.