Rows

Why we picked it 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.

Virality (k-factor) Calculator and Spreadsheet

From Rows Free web tool

• 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.