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Virality (k-factor) Calculator and Spreadsheet

Rows Free Beginner

Reading about k-factor is one thing, measuring your own is another. This is a plug-in-your-numbers spreadsheet: enter your user base, invites sent, and signups from those invites, and it returns your actual K instead of a guess. Open the full spreadsheet if you want to edit the formulas and model a few scenarios yourself.

  • Computes your real k-factor from three inputs you already have: total users, invites sent, and signups from invites.
  • Because it is a spreadsheet you can copy, you can extend it to model cycle time or different conversion rates and see how growth compounds.
  • Best used per cohort (invites divided by that cohort, signups divided by those invites) rather than across your whole base, which keeps the number honest.
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The question it answers

  1. What's a viral coefficient, and is chasing a k-factor above 1 realistic for my kind of product?

Read with it

  1. This is the piece nearly every later explainer is quoting from, so start at the source. Skok lays out the actual math (K =... For Entrepreneurs Essay · ~15 min read Lessons Learned: Viral Marketing David Skok
  2. This is the honest counterweight to the hype in your question. It states plainly that a K-factor above 1 is rare, then backs it... Saxifrage Blog Article · ~10 min read K-Factor Benchmarks Michael Taylor
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