PureBuild is a collection of free, deterministic calculators designed for startup founders and builders. Our tools help you make data-driven decisions about equity, dilution, runway, unit economics, and more.

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What tools does PureBuild offer?

PureBuild offers 9+ specialized calculators including: Equity Calculator, Dilution Simulator, Runway Calculator, Unit Economics Modeler, Payment Gateway Fee Calculator, API Token Cost Estimator, Database Capacity Planner, Viral Coefficient Calculator, and True Hourly Rate Calculator.

What is a good viral coefficient?

K > 1 is viral (exponential growth). K = 0.5-1.0 is good for supplementing paid acquisition. K 2.

How do I improve my viral coefficient?

Increase invites by making sharing frictionless and rewarding. Improve conversion by optimizing the invite landing page, adding social proof, and offering incentives to both referrer and referee.

What's the difference between viral coefficient and viral cycle time?

K-factor is how many users each user brings. Viral cycle time is how long it takes. Fast cycle time (days) with K > 1 = explosive growth. Slow cycle time (months) means slower but sustainable growth.

What is a good viral coefficient?

K > 1 is viral (exponential growth). K = 0.5-1.0 is good for supplementing paid acquisition. K 2.

How do I improve my viral coefficient?

Increase invites by making sharing frictionless and rewarding. Improve conversion by optimizing the invite landing page, adding social proof, and offering incentives to both referrer and referee.

What's the difference between viral coefficient and viral cycle time?

K-factor is how many users each user brings. Viral cycle time is how long it takes. Fast cycle time (days) with K > 1 = explosive growth. Slow cycle time (months) means slower but sustainable growth.

Viral Coefficient Calculator: K-Factor & Viral Growth Projection

PUREBUILD VC-9000

INVITES PER USERINPUT MODE

PROGRESS0/2 REQUIRED

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50,000+ calculations

Last updated: 2025-01

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Frequently Asked Questions

Viral coefficient (K-factor) measures how many new users each existing user brings in. K = invites per user × conversion rate. K > 1 means exponential growth, K < 1 means the product needs paid acquisition.

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