GrowthAdvanced

Virality (K-factor)

How much your users bring in new users by themselves. A K-factor above 1 means each user brings more than one new user — organic, self-fuelling growth.

Example

If each user invites 3 friends and 40% join, K = 1.2 — the product grows on its own.

Formula

K-factor = Invites Sent per User × Invite Conversion Rate

Related terms

North Star Metric

The single number that best captures the value your product delivers — the one metric the whole team rallies around.

Conversion Rate

The share of people who take the action you want — sign up, buy, subscribe — out of everyone who had the chance.

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